AGRICULTURAL    ENGINEERING     SERIES 
E.   B.   McCORMICK,   CONSULTING  EDITOR 

MECHANICAL    ENGINEER,   OFFICE    OF    PUBLIC    ROADS 

U.  8.  DEPARTMENT    OF   AGRICULTURE 

FORMERLY    DEAN    OF    ENGINEERING    DIVISION 

KANSAS   STATE   AGRICULTURAL   COLLEGE 


USE  OF  WATER  IN  IRRIGATION 


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I 


USE  OF  WATER 

IN 

IRRIGATION 


BY 

SAMUEL  FORTIER,  D.  Sc. 

CHIEF    OF    IRRIGATION    INVESTIGATIONS,  OFFICE    OF    EXPERIMENT    STATIONS 


U.   8.    DEPARTMENT    OF     AGRICULTURE 


FIRST  EDITION 


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239  WEST  39TH  STREET,  NEW  YORK 

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1915 


COPYRIGHT,  1915,  BY  THE 
McGRAW-HiLL  BOOK  COMPANY,  INC. 


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Co 

THE   MEMORY    OF 
MY   MOTHER 


300313 


PREFACE 

IT  is  well  to  recognize  at  the  outset  that  irrigation  is  a  many- 
sided  subject.  The  heavy  drafts  which  it  makes  on  scanty 
water  supplies  and  the  close  relationship  which  it  bears  to  other 
uses  of  water  call  for  wise  legislation  and  efficient  control  on 
the  part  of  state  governments  in  the  granting  and  protection 
of  water  rights  and  the  equitable  distribution  of  water  supplies. 
These  comprise  the  legal  and  administrative  features  of  irriga- 
tion. Again,  enormous  quantities  of  water  have  tof  be  annu- 
ally stored  in  the  mountains,  pumped  from  wells,  diverted 
from  torrential  streams,  conveyed  around  hills  and  across  valleys 
and  finally  delivered  to  farmers.  The  accomplishment  of  so 
great  a  task  calls  for  high  ability  and  broad  experience  on  the 
part  of  engineers  in  designing  and  constructing  the  needed  works 
and  these  constitute  the  engineering  side  of  irrigation.  Then  there 
is  the  agricultural  side  of  irrigation  which  transcends  all  others 
in  importance,  in  that  it  deals  with  the  production  of  profitable 
crops.  All  other  phases  of  irrigation  are  but  means  to  an  end. 
The  one  great  purpose  is  to  transform  desert  places  into  gardens 
and  orchards  where  the  highest  type  of  American  citizens  may 
establish  homes.  Lastly,  running  all  through  the  subject  like 
threads  in  a  fabric,  are  to  be  found  such  features  as  proper 
organization,  cooperation,  good  management  and  profitable 
returns.  These  may  be  grouped  under  the  economic  side  of 
irrigation. 

Xo  work  on  American  Irrigation  would  be  complete  that 
did  not  embrace  all  of  these  salient  features.  On  the  other  hand, 
the  time  required  to  prepare  so  much  material  would  cause  the 
first  part  to  be  out  of  date  before  the  last  was  written.  So 
it  has  been  deemed  best  to  consider  but  one  phase  of  the  subject 
at  a  time  and  to  publish  the  material  which  properly  belongs  to 
that  phase  in  a  separate  volume. 

The  volume  here  presented  deals  with  the  agricultural  side 
of  irrigation  under  the  somewhat  broad  title,  Use  of  Water 
in  Irrigation.  It  aims  to  benefit  at  least  three  classes  of  readers. 

vii 


viii  PREFACE 

The  first  comprises  the  new  settlers  and  those  who  are  look- 
ing to  the  West  as  a  suitable  place  to  establish  homes.  The 
second  includes  the  irrigation  farmers  and  those  who  are  in- 
terested in  irrigated  agriculture;  and  the  third  class  comprises 
students  in  agricultural  high  schools  and  in  the  agricultural 
and  engineeiing  classes  of  colleges  and  universities.  The  sub- 
ject matter  is  confined  almost  exclusively  to  the  irrigated  farm 
and  to  the  problems  which  confront  the  irrigator.  In  this 
respect  it  is  an  Irrigator's  Handbook.  The  legal,  economic 
and  engineering  phases  of  the  subject  are  touched  upon  but  only 
insofar  as  they  affect  the  welfare  of  the  farmer.  Considerable 
space  has  been  given  to  methods  of  preparing  land  and  ap- 
plying water  for  the  reason  that  the  manner  in  which  these 
are  done  determines  to  a  large  degree  the  profits  derived  by 
the  farmers  and  the  success  of  canal  companies.  Considering 
the  rich  soil  and  favorable  climate  of-  arid  America,  the  aver- 
age yields  under  irrigation  are  small.  This  is  mainly  due  to 
the  adoption  and  use  of  faulty  methods  in  watering  fields  and 
maintaining  moisture  conditions  in  the  soil.  It  is  hoped  that 
out  of  the  many  methods  herein  described  the  farmer  may  adopt 
those  best  suited  to  the  conditions  on  his  farm  and  thus  pave 
the  way  for  profitable  returns. 

The  manner  in  which  water  is  used  in  irrigation  as  described 
in  these  pages  is  nation-wide.  The  same  care  and  attention 
which  were  paid  to  the  irrigation  of  cotton  and  sugar  cane  in 
the  Southwest,  to  rice  in  the  Gulf  States  and  to  truck  and  fruit 
crops  along  the  Atlantic  seaboard  were  given  to  the  irriga- 
tion of  forage  and  cereal  crops  in  the  Mountain  States  and  to 
vineyards  and  orchards  along  the  Pacific.  To  cover  so  wide 
a  field  is  much  beyond  the  range  of  experience  of  any  one  man 
and  in  this  connection  the  author  gratefully  acknowledges 
the  assistance  rendered  by  members  of  the  Division  of  Irriga- 
tion Investigations  of  the  Office  of  Experiment  Stations,  U.  S. 
'Department  of  Agriculture.  For  more  than  a  dozen  years  this 
faithful  band  of  technically  and  scientifically  trained  men 
have  worked  with  and  for  the  irrigators  in  their  efforts  to  in- 
crease the  productivity  of  land,  establish  homes  and  create 
more  prosperous  farming  communities  through  the  agency  of 
water  wisely  used.  Whatever  of  merit  this  publication  may 


PREFACE  ix 

possess  is  due  in  the  main  to  the  writings  and  views  of  these  co- 
workers  in  the  development  of  irrigation  in  this  country.  It 
records  the  experiences  gained  in  the  field  and  laboratory  rather 
than  what  may  be  compiled  in  a  library. 

The  author  likewise  desires  to  acknowledge  his  indebtedness 
to  the  HONORABLE  DAVID  F.  HOUSTON,  Secretary  of  Agriculture, 
for  permission  to  publish  this  Handbook  and  to  DR.  A.  C.  TRUE, 
Director  of  the  Office  of  Experiment  Stations,  for  permission  to 
make  use  of  the  publications  and  illustrations  of  the  Office. 

S.  F. 

WASHINGTON,  D.  C., 
December,  1914. 


CONTENTS 

PREFACE PAGE     vii 

LIST'OP  PLATES  .  xiii 


CHAPTER  I 
INTRODUCTION 

Extent  of  Irrigation  in  the  United  States PAGE       1 

Agencies  in  Irrigation  Development 

Cost  of  Irrigation  in  the  United  States 3 

CHAPTER  II 
THE  IRRIGATED  FARM 

ART.     1.  Location  and  Selection  of  a  Farm  under  Irrigation   .    .  PAGE       7 

2.  Lands  Open  to  Settlement  by  Purchase  or  Entry  ...  9 

3.  Water  Supplies 11 

4.  Water  Rights 13 

5.  Soils  of  the  Arid  and  Semi- Arid  Regions 18 

6.  Soil  Moisture 21 

7.  Movement  of  Soil  Moisture 24 

CHAPTER  III 
THE  NECESSARY  EQUIPMENT  AND  STRUCTURES 

8.  Equipment  for  the  New  Settler PAGE    28 

9.  Laying  out  a  Farm  under  an  Irrigation  System  ....  30 

10.  Farm  Ditches 32 

11.  Irrigation  Structures  for  the  Farm 39 

12.  Pipes  and  Pipe  Systems  for  the  Farm 47 

13.  Pumping  Plants 57 

CHAPTER  IV 
METHODS  OF  PREPARING  LAND  AND  APPLYING  WATER 

ART.  14.  The  Removal  of  Native  Vegetation PAGE     64 

15.  Preparing  the  Surface  for  Irrigation 68 

16.  Furrow  Method  of  Irrigation 72 

xi 


Xli  CONTENTS 

17.  Corrugation  Method  of  Irrigation 80 

18.  Flooding  Method  of  Irrigation       83 

19.  Surface  Pipe  Method  of  Irrigation 84 

20.  Border  Method  of  Irrigation 87 

21.  Check  Method  of  Irrigation 91 

22.  Basin  Method  of  Irrigation 93 

23.  Subirrigation 95 

24.  Spray  Irrigation 102 

CHAPTER  V 
WASTE,  MEASUREMENT,  DELIVERY  AND  DUTY  OF  WATER 

ART.  25.  The  Low  Efficiency  of  Irrigation  Water PAGE  110 

26.  Waste  of  Water  due  to  Seepage  and  Other  Causes.  .    .  Ill 

27.  Measurement  of  Water 115 

28.  Evaporation  from  Water  Surfaces 125 

29.  Evaporation  from  Irrigated  Soils 128 

30.  The  Duty  of  Water  in  Irrigation 134 

31.  Delivery  of  Water 150 

32.  Injurious  Mineral  Salts 160 

33.  The  Use  of  Saline  Waters  in  Irrigation 162 

34.  Drainage  of  Irrigated  Farm  Lands 166 

CHAPTER  VI 
IRRIGATION  OF  STAPLE  CROPS 

ART.  35.  Alfalfa  and  Other  Forage  Crops PAGE  174 

36.  Irrigation  of  Grain 186 

37.  Growing  Root  Crops  under  Irrigation 195 

38.  Irrigation  of  Orchards 209 

39.  Irrigation  of  Rice 220 

40.  The  Growing  of  Cotton  under  Irrigation 232 

41.  The  Growing  of  Sugar  Cane  under  Irrigation .    ....  238 

42.  Irrigation  of  Onions 243 

43.  Irrigation  of  Grapes 245 

44.  Irrigation  of  Small  Fruit 247 

45.  Supplemental  Irrigation  on  the  Atlantic  Coast .      .    .    .  252 

46.  Dry  Farming  in  its  Relation  to  Supplemental  Irrigation .  253 
INDEX  .  259 


LIST  OF  PLATES 

Frontispiece. — Orange  Orchard  and  Residence  of  Mr.  J.  H.  Williams, 

Porterville,  Cal Frontis. 

FACING   PAGE 

PLATE  II 76 

Fig.  A. — Laying  concrete  pipe. 
Fig.  B. — Setting  stands. 

PLATE  III 96 

Fig.  A. — Main  line  and  stop-boxes  for  subirrigation  systems. 
Fig.  B. — Lateral  line  and  stop-box. 
Fig.  C. — Details  of  stop-boxes. 

PLATE  IV '  .    .    104 

Fig.  A. — Overhead  spray  irrigation  showing  piping. 
Fig.  B. — Enlarged  view  of  overhead  nozzle  line. 

PLATE  V 116 

Fig.  A. — Downstream  view  of  trapezoidal  wire  in  use. 

Fig.  B. — Upstream  view  showing  measurement  being  taken. 

Fig.  C. — Automatic  water  register. 

PLATE  VI 126 

Fig.  A. — Testing  Australian  meter  against  standard  weir. 
Fig.  B. — Similar  device  used  in  Victoria,  Australia. 

PLATE  VII 149 

Fig.  A. — Equipment  used  for  determining  the  water  requirements 
of  crops. 

Figs.  B  and  C. — Equipment  used  for  determining  the  water  re- 
quirements of  crops. 


Xlll 


USE  OF  WATER  IN  IRRIGATION 


CHAPTER  I 
INTRODUCTION 

Those  who  have  watched  the  rise  and  progress  of  Western 
commonwealths  must  have  observed  how  large  a  part  of  their  total 
revenue  is  derived  from  irrigated  products.  Irrigated  agri- 
culture lies  at  the  foundation  of  much  of  the  material  prosperity 
of  the  West.  Through  the  agency  of  water  wisely  used,  deserts 
are  converted  into  productive  fields  and  orchards,  and  flocks 
and  herds  and  prosperous  communities  take  the  place  of  wild 
animals  and  an  uncivilized  race.  It  also  furnishes  food  and 
clothing  for  the  dwellers  in  cities,  raw  material  for  the  manu- 
facturer and  traffic  for  the  transportation  company.  If  it  were 
possible  to  remove  from  the  arid  region  the  comparatively  small 
area  which  has  been  rendered  highly  productive  by  means  of  ir- 
rigation, it  would  go  far  to  undo  the  labor  of  half  a  century 
in  building  up  the  western  half  of  the  Union. 

Extent  of  Irrigation  in  the  United  States. — The  extent  of 
irrigation  in  the  United  States  is  shown  in  the  following  table 
compiled  from  Census  data.  The  first  column  of  figures  gives 
the  acreage  actually  irrigated  in  1909,  in  each  of  the  seventeen 
western  states,  the  Gulf  states  and  throughout  the  humid  region, 
the  second  column  the  acreage  which  the  enterprises  were  capable 
of  irrigating  in  1910  and  the  third  column  the  acreage  included 
in  enterprises  either  completed  or  under  way  July  1,  1910.  In 
the  last  column  of  the  table  is  given  the  estimated  value  of 
irrigated  crops  in  each  of  the  seventeen  western  states  and  also 
in  the  rice  belt  of  the  Gulf  states. 

1 


'USE  &F  WATER  IN  IRRIGATION 


TABLE  No.  1 


State 

Acreage 
irrigated 
in  1909 

Acreage 
enterprises 
were  capable 
of  irrigating 
in  1910 

Acreage 
included  in 
enterprises 

Estimated 
value  of 
irrigated 
crops  in 
19101 

Arizona 

320,051 

387,655 

944,090 

$5,765,030 

California  
Colorado  
Idaho  

2,664,104 
2,792,032 
1,430,848 

3,619,378 
3,990,166 

2,388,959 

5,490,360 
5,917,457 
3,549,573 

70,849,320 
56,312,392 
27,684,194 

Kansas.        

37,479 

139,995 

161,300 

1,781,617 

Montana 

1,679,084 

2,205,155 

3,515,602 

19,040  620 

Nebraska  

255,950 

429,225 

680,133 

3,335,328 

Nevada.            

701,833 

840,962 

1,232,142 

9,910,080 

New  Mexico 

461,718 

644,970 

1,102,297 

7,997  628 

North  Dakota  

10,248 

21,917 

38,173 

120,483 

Oklahoma.               .  . 

4,388 

6,397 

8,528 

88,851 

Oregon  

686,129 

830,526 

2,527,208 

9,104,225 

South  Dakota  
Texas.. 

63,248 
164,283 

128,481 
340,641 

201,625 
753,699 

1,031,388 
5,416  346 

Utah  
Washington  
Wyoming 

999,410 
334,378 
1,133,302 

1,250,246 
470,514 
1,639,510 

1,947,625 
817,032 

2,224,298 

18,317,086 
11,251,647 
10  750  592 

Gulf  States.  
Humid  Region.   .  .  . 

694,800 
30,000 

950,706 
30,000 

950,706 
30,000 

15,000,000 
3,000,000 

Total  

14,463,285 

20,315,403 

32,091,848 

276,756,827 

Agencies  in  Irrigation  Development. — Out  of  a  total  of  over 
14,000,000  acres  the  individual  irrigator  who  has  either  built  a 
ditch  himself  or  formed  a  partnership  with  one  or  more  neighbors 
has  reclaimed  and  irrigated  6,624,614  acres.  Next  in  order  come 
the  cooperative  companies  which  are  really  larger  groups  of  farm- 
ers acting  together  in  building  the  necessary  works.  Next  come 
the  commercial  enterprises  of  one  sort  or  another  which  have 
launched  into  the  business  of  furnishing  a  water  right  and  selling 
it  to  the  irrigator.  Public  irrigation  corporations  known  as 
irrigation  districts,  the  U.  S.  Reclamation  Service,  companies 
operating  under  the  Carey  Act,  and  the  U.  S.  Indian  Service, 
comprise  the  remainder  of  these  agencies.  The  extent  of  land 
which  was  reclaimed  by  each  of  these  agencies  at  the  close  of 
1909  is  given  in  the  following  table.2 

1  Compiled  by  P.  A.  Ewing,  formerly  connected  with  the  Irrigation  Census. 

2  Irrigation  in  the  United  States  by  R.  P.  Teele,  13th  Census. 


INTRODUCTION 


TABLE  No.  2 


Agency 

Acres 

Individual  and  Partnership  Enterprises 

6,624,614 

Cooperative  Enterprises  

4,643,539 

Commercial  Enterprises.                        

1,809,379 

Irrigation  Districts 

528,642 

U  S  Reclamation  Service  

395,646 

Carey  Act  Enterprises  
U  S  Indian  Service 

288,553 
172,912 

14,463,285 


Cost  of  Irrigation  in  the  United  States. — The  total  cost  of 
irrigation  falls  naturally  into  two  divisions.  One  of  these  rep- 
resents the  cost  of  the  works  necessary  to  provide  a  water  supply 
and  to  convey  it  to  within  easy  reach  of  each  farm.  The  other 
represents  the  cost  of  preparing  the  land  in  such  a  way  that  it  can 
be  irrigated  together  with  the  cost  of  farm  ditches  and  structures. 

The  cost  of  irrigation  works  for  each  western  state  up  to 
July  1,  1910,  as  found  by  the  Census  is  given  in  Table  3  and 

TABLE  No.  3 


State 

Average 
cost  per 
acre  of 
preparing 
land 

Cost  of  works 
to  July  1,  1910 

Estimated  cost 
of  preparing 
land  irrigated 
in  1909 

Total  estimated 
cost 

Arizona. 

$13.75 

$17,677,966 

$4,401,000 

$22,078,966 

California 

19  25 

72,580,030 

51,284,000 

123,864,030 

Colorado.. 

14.50 

56,636,443 

40,485,000 

97,121,443 

Idaho  

11.60 

40,977,688 

16,598,000 

57,575,688 

Kansas  
Montana  
Nebraska  
Nevada 

10.50 
12.50 
10.50 
10  00 

1,365,563 
22,970,958 
7,798,310 
6,721,924 

394,000 
20,989,000 
2,687,000 
7,018,000 

1,759,563 
43,959,958 
10,485,310 
13,739,924 

New  Mexico.  .  .  . 
North  Dakota.  .  . 
Oklahoma 

13.50 
11.00 
10  50 

9,154,897 
836,482 
47,200 

6,233,000 
113,000 
46,000 

15,387,897 
949,482 
93,200 

Oregon  

15.00 

12,760,214 

10,292,000 

23,052,214 

South  Dakota... 
Texas  

12.00 
19.00 

3,043,140 
7,346,708 

759,000 
3,121,000 

3,802,140 
10,467,708 

Utah  

15.00 

14,028,717 

14,990,000 

29,018,717 

Washington  
Wyoming 

16.00 
9  00 

16,219,149 
17  700,980 

5,350,000 
10,200,000 

21,569,149 
27,900,980 

Totals  

$307,866,369 

$194,960,000 

$502,826,369 

USE  OF  WATER  IN  IRRIGATION 


amounts  in  the  aggregate  to  $307,866,369.  The  estimated 
final  cost  of  such  works  when  all  the  enterprises  which  were 
either  completed  or  under  way  in  1910  are  included,  is  given  in 
Table  4  and  aggregates  $424,281,186. 

The  various  items  of  cost  comprised  in  the  second  division 
were  estimated  by  the  state  agents  of  Irrigation  Investigations, 
Office  of  Experiment  Stations,  U.  S.  Department  of  Agriculture, 
located  in  the  states  where  irrigation  is  practised.  These  were 
based  on  the  amount  of  money  expended  by  farmers  in  clear- 
ing the  land  of  desert  growths,  plowing,  leveling  and  grading  it, 
building  the  necessary  supply  and  farm  ditches  with  their 
accompanying  structures  and  in  general  preparing  the  land  for 
irrigation  and  profitable  crops.  Table  No.  3  gives  the  average 

TABLE  No.  4 


Average 

State 

cost  per 
acre  of 

Estimated  final 
cost  of  works 

Estimated  final 
cost  of  preparing 

Total  estimated 
final  cost 

preparing 

land  in  projects 

land 

Arizona. 

$13.75 

$24,828,868 

$12,981,000 

$37,809,868 

California 

19.25 

84,392,344 

105,689,000 

190,081,344 

Colorado  

14.50 

76,443,239 

85,803,000 

162,246,239 

Idaho  

11.60 

58,451,106 

41,175,000 

99,626,106 

Kansas  

10.50 

1,365,563 

1,694,000 

3,059,563 

Montana  

12.50 

32,382,077 

43,945,000 

76,327,077 

Nebraska  

10.50 

9,485,231 

7,141,000 

16,626,231 

Nevada  

10.00 

12,188,756 

12,321,000 

24,509,756 

New  Mexico.  .  .  . 

13.50 

11,640,091 

14,881,000 

26,521,091 

North  Dakota.  .  . 

11.00 

836,482 

420,000 

1,256,482 

Oklahoma  

10.50 

47,200 

90,000 

137,200 

Oregon 

15.00 

39,216,619 

37,908,000 

77,124,619 

South  Dakota  .  .  . 

12.00 

3,800,556 

2,420,000 

6,220,556 

Texas  

19.00 

8,613,533 

14,320,000 

22,933,533 

Utah  

15.00 

17,840,775 

29,214,000 

47,054,775 

Washington  

16.00 

22,322,856 

13,072,000 

35,394,856 

Wyoming  

9.00 

20,425,890 

20,019,000 

40,444,890 

Totals  

$424,281,186 

$443,093,000 

$867,374,186 

cost  per  acre  of  such  preparation  in  each  of  the  western  states. 
The  product  of  this  unit  cost  and  the  acreage  irrigated  in  1909 
is  likewise  given  in  the  table  for  each  western  state  and  com- 
prise in  the  aggregate  the  sum  of  $194,960,000. 
In  estimating  the  cost  of  preparing  land  for  enterprises  not 


INTRODUCTION  5 

completed  in  1909  the  same  unit  costs  were  used.  These  when 
multiplied  by  the  number  of  acres  contained  within  completed 
and  incompleted  enterprises  are  given  in  Table  No.  4  and  com- 
prise a  total  expenditure  by  the  farmers  under  irrigation  enter- 
prises, inclusive  of  the  amount  expended  for  like  purposes  prior 
to  1910  of  $443,093,000  or  $18,811,814  more  than  the  entire 
cost  of  the  construction  of  irrigation  works. 

Many  will  be  surprised  to  learn  of  the  large  expenditures 
necessary  before  the  business  of  irrigation  farming  can  be  suc- 
cessfully carried  on.  These  data  show  that  water  rights  prior 
to  1910  cost  on  an  average  62  per  cent,  of  the  total  and  that  the 
final  cost  will  be  below  50  per  cent,  of  the  total,  the  balance 
being  expended  in  the  building  of  ditches  and  structures  on  the 
farm  and  in  grading  and  smoothing  the  surfaces  of  fields  to 
permit  the  proper  application  of  irrigation  waters.  They  like- 
wise show  the  large  expenditure  necessary  in  each  western  state 
before  the  land  included  in  projects  and  not  irrigated  in  1909 
is  made  remunerative. 

The  people  of  this  country  have  been  greatly  interested  in 
the  construction  of  works  to  reclaim  desert  lands.  Land  agents 
and  others  engaged  in  the  settlement  of  these  lands  have  fostered 
this  interest  by  magnifying  the  importance  of  such  works  and  at 
the  same  time  ignoring  the  heavy  expense  which  has  to  be  in- 
curred by  the  settler  before  such  lands  can  be  made  productive. 
The  erroneous  impressions  which  have  been  formed  in  the  minds 
of  credulous  people  by  land  agents  and  press  agents  in  giving 
out  one-sided  information  by  means  of  circulars,  press  notices 
and  illustrated  lectures,  have  been  the  indirect  cause  of  great 
suffering  and  disappointment  among  the  settlers  of  irrigation 
projects  and  of  irreparable  loss  to  capital  invested  in  irrigation 
enterprises. 

This  volume  will  have  served  a  useful  purpose  if  it  corrects 
some  of  these  erroneous  impressions.  It  is  thought  no  one  can 
peruse  its  pages  without  being  impressed  with  the  large  amount 
of  money  which  must  be  expended  between  the  time  water  is 
ready  to  be  delivered  and  the  time  when  the  farm  is  on  a  paying 
basis.  The  information  which  it  contains  has  been  prepared 
with  the  object  of  assisting  the  irrigator  in  the  design  and  exe- 
cution of  that  part  of  the  work  which  he  must  perform.  The 


6  USE  OF  WATER  IN  IRRIGATION 

measure  of  his  success  will  represent  the  measure  of  the  success 
of  the  irrigation  enterprise  of  which  he  forms  a  part  since  it  is 
the  labor  of  the  irrigators  skillfully  directed  which  determines 
the  value  of  such  properties. 


CHAPTER  II 
THE  IRRIGATED  FARM 

1.  Location  and  Selection  of  a  Farm  under  Irrigation. — The 
prospective  settler  usually  decides  upon  the  kind  of  farming  which 
he  wishes  to  follow,  basing  his  decision  upon  the  experience  and 
knowledge  of  various  phases  of  the  subject  which  he  has  acquired. 
Having  arrived  at  this  decision  he  should  then  seek  for  a  suitable 
location. 

The  selection  of  a  farm,  to  be  operated  under  irrigation,  should 
be  made  only  after  carefully  investigating  the  climate,  soil, 
drainage,  crops  to  be  raised,  transportation  facilities  to  local  and 
distant  markets,  and  the  social  and  educational  advantages  of 
the  various  localities.  Since  health  is  paramount  all  malaria 
and  fever  infested  districts  should  be  shunned  no  matter  how 
many  advantages  they  possess  in  other  respects.  Except  where 
health  must  be  considered  climatic  conditions  in  general  should 
only  be  given  the  same  weight  as  the  other  factors  involved. 
These  conditions  are  different  throughout  the  various  sections 
of  the  country  and  will  be  found  to  vary  for  even  a  given  locality. 
In  the  valleys  and  lowlands  frost  occurs  later  in  the  spring  and 
earlier  in  the  fall  than  upon  the  adjacent  ridges  and  tablelands 
thus  producing  a  slightly  shorter  growing  season  for  the  same 
locality.  The  decision  regarding  the  kind  of  farming  to  be 
followed  will  usually  determine  the  section  of  the  country  to  be 
investigated. 

Special  consideration  should  be  given  to  the  character  of  the 
soil  since  all  plants  require  certain  nutrients  to  sustain  life. 
These  must  be  present  in  the  soil  in  an  available  form  before  crops 
can  be  successfully  grown.  When  the  supply  of  plant  food  is 
not  available  or  is  deficient  in  some  elements  the  defect  can  be 
remedied  only  by  skillful  treatment  or  the  application  of  artificial 
fertilizers  at  the  expense  of  labor  and  capital.  Only  those  soils 
which  contain  plenty  of  plant  food  should  be  selected. 

The  surface  and  subsurface  conditions  of  the  soil  should  Jike- 

7 


8  USE  OF  WATER  IN  IRRIGATION 

wise  be  considered.  A  surface  with  knolls  and  hollows  requires 
leveling  for  irrigation.  Leveling  involves  the  remoyal  of  earth 
from  the  knolls  and  the  filling  in  of  the  hollows,  thus  the  rougher 
the  surface  the  more  costly  will  be  its  preparation  for  irrigation. 
An  ideal  farm  for  irrigation  should  have  an  even  surface  which 
slopes  uniformly  in  one  or  two  directions.  Land  with  a  good 
surface  slope  has  two  advantages,  it  is  easily  irrigated  and  readily 
drained.  Formerly  drainage  was  given  little  consideration  but 
the  consequences  resulting  from  continuous  irrigation  show  that 
irrigated  land  must  have  proper  drainage.  Should  the  soil  be 
underlaid  with  an  impervious  stratum  excessive  applications  of 
water  may  raise  the  water  table  and  damage  crops.  The  con- 
tinual evaporation  would  likewise  precipitate  the  salts,  which 
have  been  dissolved  out  of  the  soil,  upon  the  surface  and  im- 
pregnate the  surface  with  alkali.  A  porous  subsoil  would  allow 
all  excess  water  applied  to  the  land  to  pass  downward  and  thus 
prevent  injurious  results.  On  the  other  hand,  too  porous  a  soil 
may  waste  valuable  water  through  deep  percolation. 

Both  soil  and  climatic  conditions  should  be  studied  for  the 
purpose  of  determining  what  crops  can  best  be  grown  under 
these  conditions.  The  crops  grown  in  a  newly  developed 
district  are  usually  a  poor  guide  since  they  are  consumed  at 
home  or  within  the  district.  Under  such  conditions  prices  are 
usually  high  whereas  if  an  extensive  area  be  planted  to  these 
same  crops  the  local  price  may  fall  so  low  that  it  will  not  be 
profitable  to  produce  them. 

It  is  thus  apparent  that  the  selection  of  profitable  crops  to  be 
grown  involves  a  study  of  transportation  facilities  and  a  proximity 
to  outside  markets.  If  crops  have  to  be  shipped  long  distances 
attention  must  be  given  to  the  selection  of  those  which  will  sell 
for  a  relatively  high  price  per  pound  or  else  the  freight  charges 
may  consume  all  possible  profits.  Bulky  crops  which  sell  for  a 
small  unit  price  may  be  converted  into  finished  products  on  the 
farm,  by  such  means,  for  instance  as  the  feeding  of  livestock  for 
market.  Profitable  returns  may  be  realized  in  this  way  yet 
every  mile  distant  from  the  railroad  and  likewise  from  the  open 
market  increases  the  cost  of  production.  Hence  the  farm  should 
be  located  so  that  it  is  in  reasonably  close  proximity  to  railway 
facilities  and  not  too  great  a  distance  from  good  markets. 


THE  IRRIGATED  FARM  9 

At  first  social  and  educational  advantages  are  rather  limited 
in  a  newly  developed  section.  Provisions  for  schools,  however, 
are  usually  made  a  part  of  the  administrative  policy  of  irrigation 
projects  and  they  are  established  whenever  the  attendance  is 
sufficient  to  warrant  such  institutions.  In  the  West  instances 
are  common  where  schools  were  organized  as  soon  as  some  four 
or  five  children  of  school  age  resided  within  the  district.  Schools 
are  closely  followed  by  social  and  religious  activities  which  tend 
to  the  uplift  and  betterment  of  the  community. 

At  the  beginning  the  farm  has  but  a  slight  intrinsic  value  but 
as  improvements  are  made  and  as  social  and  educational  con- 
ditions become  better,  its  value  rises.  Again,  as  the  com- 
munity becomes  better  settled  small  towns  and  villages  may 
spring  up  which  will  tend  to  enhance  its  value  still  more.  Even 
though  proximity  to  a  town  and  favorable  social  and  educational 
facilities  can  not  be  had  to  the  extent  desired  the  settler  has  it 
in  his  power  to  make  his  farm  highly  productive  and  valuable 
by  the  adoption  of  good  methods  of  farming  skillfully  carried 
out. 

Farming  under  irrigation  along  the  Atlantic  seaboard  is  at 
present  confined  to  valuable  truck  and  fruit  crops.  These  are 
usually  grown  in  the  warmer  and  earlier  sandy,  muck  or  peat 
soils  which  yield  large  returns  under  proper  treatment.  The 
essentials  of  such  treatment  are  intensive  culture,  an  abundance 
of  fertilizers  and  proper  moisture  control. 

Soil  moisture  and  frosts  are  the  most  difficult  to  control  and 
the  chief  causes  of  crop  failures.  However,  an  excess  of  moisture 
can  be  readily  removed  by  tile  drainage  and  any  deficiency  can 
as  readily  be  supplied  by  irrigation.  The  dangers  from  frost 
can  be  greatly  lessened  by  selecting  the  right  location  and  by 
maturing  the  crops  with  the  least  delay.  It  is  in  this  connection 
that  irrigation  plays  an  important  part.  By  its  means  the 
seed  bed  can  be  prepared  and  the  seed  planted  regardless  of  dry 
weather.  A  light  irrigation  at  the  right  time  also  keeps  the 
plants  in  a  vigorous  condition  until  maturity. 

2.  Lands  Open  to  Settlement  by  Purchase  or  Entry. — Before 
acquiring  western  land  the  prospective  settler  should  first  con- 
sider the  opportunities  to  which  his  circumstances  make  him 
eligible.  If  he  has  money  or  credit  he  may  purchase  an  improved 


10  USE  OF  WATER  IN  IRRIGATION 

farm  in  one  of  the  older  districts.  The  price  of  fertile  and  im- 
proved farms  with  a  reliable  water  right  varies  between  wide 
limits.  Those  which  produce  good  yields  of  alfalfa,  grain  and 
root  crops  range  in  price  from  $50  to  $200  per  acre;  deciduous 
orchards,  vineyards  and  diversified  farms  near  towns  and  cities 
are  worth  from  $200  to  $500,  while  citrus  orchards  can  seldom 
be  purchased  for  less  than  $1000  per  acre. 

The  wealth  in  irrigated  farms  which  now  yield  a  yearly  revenue 
of  over  $276,000,000  was  created  by  men  who  were  poor  in  worldly 
goods  but  rich  in  those  physical  and  mental  qualities  which  go 
to  make  up  the  best  type  of  citizenship.  If  the  prospective 
settler  belongs  to  this  class  it  would  seem  wise  for  him  to  select 
a  tract  of  raw  land  and  by  the  exercise  of  brain  and  brawn 
transform  it  into  a  highly  productive  and  valuable  farm. 

To  those  who  are  equipped  with  more  vigor  and  courage  than 
cash  capital  there  is  still  good  arable  raw  land  available  in  the 
West.  Settlement  under  the  desert  land  act  is  confined  for 
the  most  part  to  localities  where  the  settler  secures  a  water  right 
from  some  canal  already  built.  The  individual  entryman  is 
seldom  able  financially  to  put  in  his  own  system  of  irrigation. 
Sometimes  this  can  be  done  by  the  union  of  several  entrymen. 
Opportunities  for  settlement  under  the  homestead  law  upon 
lands  susceptible  of  irrigation  are  at  present  few  and  hard  to 
find,  but  large  areas  acquired  under  this  law  in  the  past  are 
now  irrigated  with  water  purchased  from  canal  companies. 

To  those  who  are  unfamiliar  with  local  conditions  the  best 
openings  for  settlement  are  to  be  found  on  the  vacant  lands  in- 
cluded in  the  many  irrigation  enterprises  for  which  a  water 
supply  has  been  provided.  The  following  figures  taken  from 
the  Census  of  1910  show  the  extent  of  such  land  awaiting  reclama- 
tion and  settlement  in  that  year  under  the  agencies  named. 


Acres 

Cooperative  enterprises 4,186,658 

Commercial  enterprises 3,668,171 

Carey  Act  enterprises 2,265,321 

U.  S.  Reclamation  Service 1,677,370 

Irrigation  districts 1,052,823 


Total 12,850,343 


THE  IRRIGATED  FARM  11 

The  foregoing  figures  include  the  unirrigated  portions  of  farms 
ami  a  large  area  in  the  aggregate  which  for  one  reason  or'another 
may  never  be  irrigated.  Even  when  all  such  areas  are  deducted 
there  remains  a  vast  extent  of  land  for  which  water  has  been  pro- 
vided but  which  is  unreclaimed  for  lack  of  settlers. 

Some  information  for  the  prospective  settler  is  briefly  sum- 
marized by  F.  C.  Scobey,  Irrigation  Engineer  of  the  Office  of 
Experiment  Stations  in  the  following  schedule.  (Table  No.  5.) 
For  the  exceptions  to  the  statements  made  therein  and  for  more 
detailed  information  the  reader  is  referred  to  Circulars  6,  116, 
253,  290  and  the  general  reclamation  circular  of  the  U.  S.  Land 
Office,  all  of  which  publications  may  be  had  free  on  application. 

3.  Water  Supply. — According  to  the  13th  Census  approxi- 
mately 95  per  cent,  of  the  land  irrigated  in  1909  was  irrigated 
from  streams.  The  remainder  consisted  of  452,000  acres  ir- 
rigated from  wells,  196,000  acres  from  springs,  98,000  acres  from 
stored- water  reservoirs,  and  70,500  acres  from  lakes.  Most 
of  the  streams  used  for  irrigation  rise  in  the  higher  mountains 
and  are  fed  mostly  by  melting  snows.  This  results  in  a  flood 
flow  in  the  late  spring  and  early  summer  when  the  snows  are 
melting  rapidly  and  rains  are  occurring  in  the  lower  altitudes, 
and  a  low  flow  during  the  remainder  of  the  summer,  when  the 
only  sources  of  supply  are  the  melting  of  glaciers  and  the  last 
of  the  higher  snowbanks,  and  seepage  from  saturated  lands. 
Consequently,  nearly  all  the  streams  carry  more  water  in  the 
flood  season  than  can  be  used,  while  in  summer,  when  there  is 
the  greatest  need  for  water,  there  is  a  serious  shortage.  A 
tabulation  made  by  the  Bureau  of  the  Census  of  the  flow  in  1909 
of  twelve  of  the  largest  streams  draining  the  Rocky  Mountains 
and  the  east  side  of  the  Cascade  Range  shows  the  aggregate 
June  discharge  of  these  streams  to  have  been  nearly  four  times 
the  aggregate  August  discharge.  The  flood  discharge  of  in- 
dividual streams  is  commonly  five  to  ten  times  that  of  the  low- 
water  flow. 

The  low-water  flow  of  most  of  the  streams  of  the  arid  sec- 
tion is  utilized  by  the  present  irrigation  works,  and  the  greater 
part  of  the  future  extension  of  irrigation  will  depend  upon  the 
storage  of  the  winter  and  the  flood  flow  of  streams.  On  many 
streams,  notably  those  of  Colorado,  storage  has  been  practised 


12 


USE  OF  WATER  IN  IRRIGATION 


TABLE  No.  5 

Table   of   General   Information   Concerning  Land   Available    to   the  Pros- 
pective Settler 


•  1 

l| 

1  e? 

3-1 

Homestead 
entry 

£^ 
$% 
0  ^ 

fc  "S 

~  3 

02 
« 

cd 

p 

Who  are  qualified? 
All  citizens  of  U.  S  

Yes 

No 

No 

Yes 

Yes 

No 

Men  over  21  years 

Yes 

Yes 

Yes 

Married  women  

Yes 

No 

Yes 

Widows  or  deserted  wives 

Yes 

Yes 

Yes 

Single  women  over  21  years  

Yes 

Yes 

Yes 

Heads  of  families  under  21  yrs.. 

Yes 

Acreage  limit  to  one  settler  

None 

320 

160 

160 

None 

10- 

Is    land    assignable    before    patent 

issues? 

Yes 

No 

Yes 

160 
Yes 

Is  residence  on  land  required?  

No 

No 

Yes 

Yes 

No 

YPS 

Is  a  dwelling  required? 

No 

No 

Yes 

Yes 

No 

Yes 

Is  cultivation  of  land  required?  
Is     water     supply     for     irrigation 
required? 

No 
No 

Yes 

Yes 

Yes 
No 

Yes 
Yes 

No 
Yes 

Yes 
Yes 

Is    property    liable    for    irrigation 
charges  ?  

Yes 

Yes 

Yes 

What  time  is  allowed  before  final 
proof  in  years?  

4 

7  or  5 

3 

?0 

What  time  must  elapse  before  final 
proof  unless  commuted? 

5  or  3 

Immediate  money  necessary  per  A. 

What  is  eventual  cost  per  acre  aside 
from  labor?  

Vari- 
able 

do 

25c. 
$3.25 

Nominal 
do 

25c. 
$10-65 

do 

1st 
pay 

$30- 

May    irrigation    water    be    secured 
from: 
An  individual  or  partnership  sys- 
tem? 

Yes 

Yes 

Yes 

Yes 

Yes 

110 

No 

A  commerical  co.  system?  
A  Carey  Act  company?  

Yes 
Yes 

Yes 

Yes 

Yes 

Yes 

Yes 
Yes 

Yes 

Yes 

No 

No 

A  cooperative  company?       

Yes 

Yes 

Yes 

Yes 

Yes 

No 

An  irrigation  district? 

Yes 

Yes 

Indi- 

Yes 

No 

U.  S.  Reclamation  Service?  

Yes 

Yes 

Yes 

rectly 
do 

Yes 

Yes 

THE  IRRIGATED  FARM  13 

for  a  number  of  years.  The  Census  reported  that  in  1909  there 
were  6800  reservoirs  having  an  aggregate  capacity  of  12,581,000 
acre-feet  used  for  storing  water  for  irrigation  in  the  arid  section. 

While  much  storage  is  being  provided  for  by  Carey  Act  and 
other  projects  it  is  along  this  line  that  the  U.  S.  Reclamation 
Service  is  doing  its  most  important  work.  Its  great  storage  dams 
on  the  Salt  River  in  Arizona,  on  the  Boise  River  in  Idaho, 
on  the  North  Platte  in  Wyoming  and  in  many  other  streams 
of  the  West  have  greatly  increased  the  available  water  supply  of 
that  region. 

Next  to  the  storage  of  the  winter  and  flood  flow  of  streams, 
the  extension  of  irrigation  will  depend  upon  pumping  from 
wells  and  the  storage  of  storm  waters  in  reservoirs.  Large 
areas  of  arable  land  throughout  the  arid  sections  can  not  be 
irrigated  economically  from  streams,  but  are  underlain  at  com- 
paratively shallow  depths  with  good  supplies  of  ground  water. 
One  of  the  most  conspicuous  facts  in  the  irrigation  development 
of  the  last  few  years  has  been  the  rapid  increase  in  the  area 
irrigated  from  wells.  The  improvements  that  have  been  and  are 
being  made  in  pumps  and  pumping  machinery,  gasoline  and  other 
engines,  and  the  rapid  increase  in  the  cost  of  obtaining  water 
supplies  from  streams,  have  been  the  chief  causes  of  this  rapid 
development.  As  yet  California  is  the  only  state  in  which  the 
use  of  underground  waters  has  developed  to  such  an  extent  that 
laws  other  than  the  common  law  of  percolating  water  have  been 
applied  to  its  use. 

There  are  also  large  areas  of  arable  land,  especially  on  the 
Great  Plains,  which  can  not  be  irrigated  from  streams  but 
which  are  rolling  enough  to  afford  many  opportunities  for  small 
reservoirs  in  which  to  store  storm  waters  with  which  to  water 
small  acreages,  in  connection  with  larger  acreages  used  for  dry- 
farming  and  grazing. 

4.  Water  Rights. — The  right  to  use  the  water  of  streams, 
lakes,  etc.,  for  irrigation  and  other  purposes  is  defined  by  the 
constitutions,  statutes,  and  court  decisions  of  the  different 
states,  and  as  a  result  water  rights  vary  materially  in  the  dif- 
ferent sections.  As  Mr.  F.  G.  Harden  of  the  Department  of 
Agriculture  has  well  stated,  the  law  of  water  rights  in  all  the  arid 
states  is  in  a  formative  state  and  is  being  changed  constantly  by 


14  USE  OF  WATER  IN  IRRIGATION 

new  statutes  and  court  interpretations  with  a  view  to  better 
meeting  the  changing  conditions  and  necessities  of  the  different 
sections. 

Three  doctrines  regarding  the  source  and  nature  of  water 
rights  have  existed  in  the  arid  sections  of  the  United  States, 
and  there  are  in  existence  at  present  rights  based  upon  each  of 
these  doctrines.  In  nearly  all  the  states  there  is  some  water 
used  for  irrigation  under  the  common-law  doctrine  of  riparian 
rights.  The  rights  to  use  such  water  were  vested  at  the  time 
of  the  enacting  of  existing  water  laws,  as  the  doctrine  of  riparian 
water  rights  is  not  recognized  at  present  in  an  unmodified  form 
in  any  arid  or  semi-arid  state.  It  does  exist,  however,  in  a 
modified  form  in  California,  Kansas,  Oregon,  and  Washington. 
Under  the  common  law  riparian  rights  attach  to  all  lands  abutting 
on  a  stream,  and  the  possessor  of  such  lands  is  entitled  to  have 
the  stream  flow  by  his  land  undiminished  in  quantity  and  un- 
impaired in  quality.  Such  rights  can  not  be  lost  by  disuse  and 
can  be  separated  from  the  land  only  by  specific  grant.  Strictly 
applied,  the  doctrine  precludes  the  use  of  water  for  irrigation  and 
consequently  has  been  abandoned  or  modified  in  all  the  arid  states. 

In  Texas  and  the  states  created  out  of  the  territory  acquired 
from  Mexico  there  is  some  water  used,  the  rights  to  which  are 
based  upon  old  Spanish  or  Mexican  grants  to  individuals,  com- 
panies or  pueblos,  the  old  rights  being  recognized  by  treaties 
and  laws  of  the  United  States  and  the  states.  These  rights  vary 
widely,  as  under  the  civil  law  the  water  belonged  to  the  crown 
and  in  making  a  grant  any  restrictions  desired  could  be  placed  in 
the  grant. 

The  lands  irrigated  under  the  two  classes  of  rights  mentioned, 
however,  comprise  only  a  small  percentage  of  the  lands  under 
irrigation,  the  remainder  being  watered  under  rights  based  upon 
appropriation  and  use,  a  doctrine  originating  in  the  necessity 
and  customs  of  the  early  miners  and  irrigators.  Under  this 
doctrine  the  water  belongs  to  the  public  and  the  state  merely 
regulates  its  use,  the  right  to  make  use  of  the  water  being  ob- 
tained by  taking,  or  appropriating,  the  water,  and  putting  it  to 
a  beneficial  use.  The  right  so  gained  continues  as  long  as  the 
use  continues  and  is  not  in  conflict  with  earlier  appropriations 
from  the  same  source. 


THE  IRRIGATED  FARM  15 

Under  existing  legislation,  there  are  two  methods  of  acquiring 
water  rights.  Many  of  the  early  rights  rest  merely  on  appro- 
priation and  use  without  any  formalities  whatever.  The  only 
formalities  required  even  at  present  in  Arizona,  California, 
Kansas,  Montana,  and  Washington  are  that  a  notice  be  posted 
at  the  point  of  intended  diversion,  stating  the  amount  of  water 
claimed,  the  purpose  for  which  it  is  claimed,  the  place  of  intended 
use,  and  the  manner  in  which  the  water  is  to  be  diverted;  and 
that  a  copy  of  this  notice  be  filed  within  a  certain  time  with 
some  public  official,  usually  the  county  clerk  or  recorder.  Having 
complied  with  these  formalities,  the  appropriator  is  required  to 
begin  construction  of  his  ditch  or  other  works  within  a  specified 
time  to  prosecute  the  work  diligently  and  uninterruptedly  to 
completion,  and  to  make  beneficial  use  of  the  water.  These 
formalities  having  been  complied  with,  the  right  dates  back  to 
the  time  the  notice  was  posted.  No  records  of  construction 
or  use  are  required  to  be  filed,  and  consequently  the  records  of 
claims  are  of  little  value  in  determining  the  value  of  a  water 
right.  The  determination  of  the  value  of  such  a  right  is  made 
still  more  difficult  by  the  fact  that  the  records  in  all  the  counties 
through  which  the  stream  flows  must  be  examined,  since  claims 
may  be  filed  in  any  or  all  of  the  counties,  and  by  the  fact  that 
rights  may  be  acquired  by  diversion  and  use  without  complying 
with  any  formalities  regarding  posting  and  recording  notices. 
Such  rights,  however,  date  only  from  the  time  the  water  is  ac- 
tually put  to  beneficial  use  and  are  antedated  by  all  perfected 
rights  for  which  notices  were  posted  and  filed  before  the  water 
was  actually  put  to  use. 

In  all  the  other  states,  except  Colorado,  it  is  necessary  to 
apply  to  the  state  for  a  permit  to  appropriate  and  use  water. 
This  system  of  requiring  the  permission  of  the  state  to  appro- 
priate and  use  water  is  correctly  known  as  the  Wyoming  system. 
The  laws  of  all  the  other  states  are  modelled  after  that  of  Wyom- 
ing which  was  drafted  by  Dr.  El  wood  Mead  then  State  Engineer 
of  Wyoming.  The  data  required  in  the  applications  vary  some- 
what in  the  different  states,  but  in  general  the  following  are 
asked  for:  The  name  and  address  of  the  applicant;  the  source 
and  intended  use  of  the  water;  the  nature  of  the  ditch  or  other 
works;  maps  showing  the  location  and  extent  of  the  ditch;  the 


16  USE  OF  WATER  IN  IRRIGATION 

location  and  area  of  the  land  to  be  irrigated;  the  dates  when 
construction  will  begin  and  when  the  works  will  be  completed 
and  the  water  put  to  the  intended  use. 

The  procedure,  upon  receipt  of  the  application  by  the  state 
engineer  or  state  board  to  which  application  must  be  made,  also 
varies  somewhat  in  the  different  states,  but  in  general  is  as 
follows:  The  application  is  examined  to  ascertain  whether  it 
is  in  proper  form  and  complies  with  the  laws  and  regulations,  and  if 
so,  it  is  recorded  and  it  is  the  duty  of  the  state  engineer  or  state 
board  to  approve  the  application  and  issue  the  permit  if  there  is 
unappropriated  water  in  the  source  of  supply  provided  the 
proposed  use  will  not  impair  the  value  of  existing  rights  or  be 
detrimental  to  the  public  welfare.  The  permit  issued  by  the 
state  engineer  or  state  board  fixes  the  amount  of  water  which  may 
be  appropriated,  the  time  within  which  the  works  must  be  begun 
and  completed  and  the  waters  put  to  a  beneficial  use.  Upon 
submission  of  proof  that  the  conditions  of  the  permit  have  been 
complied  with,  a  certificate  is  issued  by  the  state  showing  what 
rights  have  been  acquired.  About  15  per  cent,  of  the  acreage 
irrigated  in  1909  was  irrigated  under  permits  or  certificates  from 
the  state,  so  small  a  percentage  being  due  to  the  fact  that  the 
laws  providing  for  this  method  of  securing  rights  have  been  on 
the  statute  books  for  only  a  few  years,  the  earliest,  that  of  Wyom- 
ing, having  been  enacted  in  1890,  and  the  most  recent,  that  of 
Texas,  in  1913. 

Although  Colorado  was  the  first  state  to  adopt  the  state 
control  of  waters,  it  does  not  require  that  any  application  for  a 
permit  to  appropriate  water,  or  that  proof  of  the  construction  of 
works  and  use  of  the  water  be  filed  with  any  state  official.  It 
does  require,  however,  that  within  60  days  after  construction 
for  the  purpose  of  appropriating  water  is  begun,  a  statement, 
together  with  maps,  must  be  filed  with  the  state  engineer,  setting 
forth  the  place  of  diversion,  the  nature  of  the  works,  the  date 
of  commencement  of  construction,  estimated  cost  of  the  project, 
etc.,  and  that  if  the  data  so  given  are  sufficient  and  satisfactory 
to  the  state  engineer,  a  copy  shall  be  filed  with  the  recorder  of 
the  county  in  which  the  headgate  is  located.  These  records 
furnish  no  index  to  the  existing  rights  to  water  from  the  same  source 
of  supply. 


THE  IRRIGATED  FARM  17 

The  adjudication  of  rights  which  are  not  denned  when  ac- 
quired is  left  to  the  courts  in  all  the  states  but  Wyoming,  Ne- 
braska, Nevada,  and  Texas,  in  which  states  it  is  left  to  adminis- 
trative boards.  The  laws  of  most  of  the  states  provide  that 
when  an  action  regarding  a  water  right  is  brought  all  parties 
having  claims  to  water  from  the  same  source  must  be  parties  to 
the  suit  so  that  the  rights  may  be  adjudicated  by  one  action. 

The  laws  of  practically  all  the  states  provide  that  water  can 
be  used  only  upon  the  land  for  which  it  is  appropriated,  conse- 
quently, when  it  is  not  being  used  upon  such  land  it  must  be 
left  in  or  turned  back  into  the  stream  for  use  of  other  appro- 
priators.  The  amount  of  water  that  can  be  beneficially  used,  is 
the  limit  in  all  the  states  of  the  amount  that  can  be  appropriated 
for  a  given  tract  of  land.  This  is  further  limited  in  most  of  the 
states  to  an  amount  not  exceeding  1  second-foot  continuous 
'flow  for  each  50,  70,  or  80  acres.  Non-use  for  a  period  of  3  to  5  years 
constitutes  an  abandonment  of  a  right  in  most  states  if  the  right  has 
been  acquired  by  appropriation  and  use. 

The  purchaser  of  a  tract  of  land  with  a  water  right  should 
exercise  as  much,  or  more,  care  in  determining  the  validity  of 
his  water  right  as  he  does  in  examining  the  title  to  his  land. 
The  few  transfers  that  have  been  made  of  the  lands  and  the  com- 
plete record  of  such  transfers  and  the  liens  against  lands  in 
the  offices  of  the  recorders  or  clerks  of  the  counties  in  most 
of  the  western  states  make  the  examination  of  the  title  to  land 
comparatively  simple.  Examinations  regarding  water  rights,  on 
the  other  hand,  are  very  complicated,  owing  to  the  various 
methods  by  which  rights  may  be  acquired,  the  lack  of  records  of 
existing  rights,  the  grounds  that  may  be  set  up  to  destroy  a 
right  or  change  its  priority,  the  fact  that  all  except  the  very 
earliest  priorities  on  the  stream  are  dependent  upon  the  low- 
water  flow,  and  the  difficulty  of  securing  proof  of  continuous  use 
and  compliance  with  laws  regarding  the  appropriation  of  water. 

According  to  the  13th  Census,  35  per  cent,  of  the  land  ir- 
rigated in  1909  was  under  rights  that  had  been  adjudicated, 
approximately  6  per  cent,  under  certificates  from  the  state,  and 
7  per  cent,  under  permits  from  the  state,  thus  making  approxi- 
mately two-fifths  of  the  acreage  under  rights  that  were  deter- 
mined as  to  extent  and  about  one-fourteenth  under  rights  that 
2 


18  USE  OF  WATER  IN  IRRIGATION 

would  be  so  determined  as  soon  as  the  appropriations  and  use 
were  completed.  The  other  half  of  the  acreage  irrigated  con- 
sisted of  2  per  cent,  under  riparian  rights,  34  per  cent,  under 
appropriation  and  use,  and  16  per  cent,  under  notices  posted 
and  filed,  all  of  which  rights  are  undefined  and  more  or  less  in- 
definite as  to  extent,  although  many  of  them  are  perfectly  valid. 
On  the  other  hand,  the  fact  that  the  right  has  been  adjudicated 
or  defined  is  not  an  absolute  guarantee  of  the  extent  or  value  of 
the  right,  as  the  appropriator  may  be  entitled  to  water  only  in 
times  of  flood,  only  when  the  flow  is  considerably  above  the 
low  summer  stage,  or  only  at  certain  periods  of  the  year;  the 
right  may  have  been  lost  or  lessened  since  the  adjudication  by 
abandonment,  and  in  some  cases  it  may  have  been  adjudicated  as 
against  only  part  of  the  other  claims  from  the  same  source  of  supply. 

5.  Soils  of  the  Arid  and  Semi-arid  Regions. — Soil  may  be 
defined  as  disintegrated  and  decomposed  rock  into  which  has 
been  incorporated  more  or  less  organic  matter  derived  from  plant 
and  animal  life.  Soils  are  of  various  chemical  and  mechanical 
composition  like  the  rocks  from  which  they  are  derived.  They 
are  popularly  classified  according  to  their  relative  sand  and 
clay  content,  as  light  or  heavy,  sandy  or  clay.  To  this  classifi- 
cation there  is  sometimes  added,  in  arid  regions,  a  third  class, 
viz.,  alkali  soils,  which  are  almost  always  of  the  heavier  type. 

In  general  it  may  be  said  that  the  soils  of  the  irrigated  sections 
of  the  United  States  are  deep,  of  high  fertility  and  uniform 
texture,  contain  large  quantities  of  lime  and  potash,  are  low 
in  humus  content  and  phosphorus  but  fairly  well  supplied  with 
nitrogen.  ,  They  allow  water  to  penetrate  readily  to  great 
depths,  contain  less  clay  and  more  sand  than  humid  soils  and 
consequently  do  not  bake  so  readily.  Arid  soils  have  much 
better  natural  drainage  than  humid  soils  but  due  to  their  great 
depth,  plant  food  is  not  leached  out  into  the  ground  water  and 
thus  lost.  The  high  per  cent,  of  lime  in  arid  soils  prevents 
sourness,  encourages  bacterial  life,  makes  some  plant  foods  more 
available,  and  aids  in  converting  organic  matter  into  humus. 
The  hard,  impervious,  non-penetrable  clay  subsoil  of  humid 
sections  is  almost  unknown  in  arid  regions  but  hardpans  are 
found  in  many  localities.  These  hardpans  are  the  result  of  a 
concentration  of  lime  and  to  a  limited  extent  of  clay  at  a  depth 


THE  IRRIGATED  FARM 


19 


below  the  surface  corresponding  to  the  limit  of  average  pene- 
tration of  the  seasonal  precipitation.  The  precipitation,  pene- 
trating the  soil  to  approximately  the  same  depth  each  yeai 
carries  in  suspension  and  in  solution  some  of  the  finer  material 
and  lime  found  in  the  top  soil.  These  substances  are  deposited 
at  about  the  same  depth  from  year  to  year  and  by  physical  and 
chemical  means  form  the  hardpan.  This  hardpan  is  almost  al- 
ways dissolved  and  destroyed  under  irrigation. 

To  describe  the  chemical  composition  of  the  average  arid 
soil  it  will  probably  be  well  to  compare  it  with  the  average 
composition  of  soils  from  humid  sections. 


TABLE  No.  6 
Chemical  Composition  of  Average  Humid  and  Arid  Soils. 


(After  Hilgard) 


Number  of 
samples 

Insolu- 
ble 
residue 

Partial  percentage  composition 

Humus 

Soluble 
silica 

Alumina 

Lime 

Potash 

Phos- 
phoric 
acid 

Humid  696  
Arid  573  '. 

84.17 

69.16 

4.04 
6.71 

3.66 
7.21 

0.13 
1.43 

0.21 
0.67 

0.12 
0.16 

1.22 
1.13 

From  the  above  table  it  is  observed  that  the  arid  soil  con- 
tains more  soluble  matter  and  more  of  the  mineral  and  plant 

TABLE  No.  7 


Class  of  soil  and 
location 

Fine 
gravel 

Coarse 
sand 

Medium 
sand 

Fine 
sand 

Very 
fine  sand 

Silt 

Clay 

Millimeters  

1-0.5 

0.5-0.250.25-0.1 

0.1-0.05 

0.05-0.005 

0.005-0 

Salt  River  clay  loam,  Ariz. 
Imperial  fine  sand,  Cal.  .  . 
Imperial  clay  loam,  Cal..  . 

Tr. 
0.00 
Tr. 

0.12 
Tr. 
0.30 

0.20 
1.20 
0.34 

13.70 
0.40 
10.26 
15.90 
0.20 
0.50 

0.30 
13.60 

1.10 

18.50 
0.60 
2.06 
1.30 
14.10 

3.80 
42.20 
1.92 

27.10 
4.30 
15.54 
39.60 
0.60 
1.40 

10.00 
30.60 

16.00 

44.20 
2.24 
5.96 
9.30 
29.80 

12.78 
38.00 
3.64 

11.90 
7.30 
11.70 
13.10 
21.30 
8.10 

48.60 
18.60 

20.70 

13.30 
14.64 
34.82 
32.60 
19.16 

42.30 
15.00 
53.90 

21.00 
64.10 
19.84 
8.40 
66.10 
71.30 

35.10 
14.20 

39.10 

11.00 
43.08 
45.04 
51.80 
13.10 

41.00 
3.58 
39.80 

10.90 
23.50 
11.26 
7.10 
11.60 
17.80 

5.50 
9.40 

22.40 

7.90 
37.80 
3.98 
4.40 
8.40 

San  Joaquin  Valley  sandy 
loam,  Cal 

1.60 
0.00 
8.96 
1.50 
0.00 
0.20 

0.10 
'3.60 

0.20 

0.40 
0.36 
1.50 
0.00 
2.80 

13.40 
0.30 
22.08 
14.50 
0.20 
0.70 

0.30 
10.30 

0.10 

7.90 
0.90 
3.08 
0.50 
12.60 

Silty  clay  loam,  Colo  
San  Luis  sandy  loam,  Colo 
Yakima  sandy  loam,  Ida. 
Colby    silt  loam,   Kansas 
Bozeman  silt  loam,  Mont. 
Finney   fine  sandy  loam, 
\ebr 

Lahontan  sandy  loam,  Nev. 
Morton       loam,       South 
Dakota    .                 

Amurillo      sandy      loam, 
Texas  

•Ionian  loam,   I'tah  

Vakinia  sandy  loam,  Wash. 
Quincy  silt  loam,  Wash.  .  . 
Laramie  sandy  loam.Wyo. 

20  USE  OF  WATER  IN  IRRIGATION 

foods  with  the  exception  of  humus.  Hilgard  determined,  how- 
ever, that  the  low  humus  content  is 'partly  compensated  by  the 
much  higher  nitrogen  content  of  the  humus  in  arid  soils  as 
compared  with  the  humus  of  soils  in  humid  sections. 

The  preceding  table  was  compiled  from  the  published  reports 
of  the  Bureau  of  Soils,  U.  S.  D.  A.  and  gives  the  mechanical 
analyses  of  typical  soils  in  various  irrigated  valleys  throughout 
the  arid  and  semi-arid  belt. 

The  soils  of  the  arid  region  will  average  about  50  per  cent,  of 
open  space.  According  to  Lyon  and  Fippin  the  pore  space  of 
various  soils  under  field  conditions  is  about  as  follows : 

Per  cent. 

Clean  sand .  33 . 5 

Fine  sand • 44.10 

Sandy  loam 51 . 00 

Silt  loam 53 . 00 

Clay  loam 54 . 00 

Clay 56.00 

"The  effect  of  irrigation  upon  arid  soils"  according  to  Professor 
W.  W.  McLaughlin  of  Utah,  "is  to  dissolve  plant  food  for  use  of  the 
plants,  to  break  up  hardpan,  to  cause  the  clay  to  become  troublesome, 
and  in  case  of  gypsum  soils  to  cause  them  to  settle.  In  alkali  soils 
the  results  of  irrigation  may  be  beneficial  or  detrimental,  depending 
upon  drainage.  The  water,  in  penetrating  an  alkali  soil  dissolves  the 
salts  and  carries  them  downward  into  the  soil.  After  each  irrigation 
part  of  the  water  previously  applied  is  drawn  upward  by  evaporation 
and  transpiration  and  the  salts  are  deposited  at  or  near  the  surface.  If 
this  process  be  continued  there  may  finally  be  such  a  concentration  of 
salts  at  the  surface  as  to  injure  or  entirely  prevent  plant  growth  and  the 
land  is  then  said  to  be  'alkalied.'" 

In  selecting  a  soil  in  the  arid  region  the  following  points  should 
be  kept  in  mind:  A  growth  of  sagebrush,  bunch  grass,  tree  and 
brush  growth  are  indexes  of  a  fertile  soil,  while  a  growth  of  shad 
scale,  salt  grass  and  other  alkali-tolerating  vegetation  indicates 
a  soil  which,  while  it  may  be  fertile,  may  contain  alkali  salts  in 
such  quantities  as  to  become  troublesome  under  irrigation  and 
especially  unless  great  care  is  taken  in  the  application  of  water. 
The  mechanical  appearance  of  the  soil,  the  way  it  feels  in  the 
hand,  its  taste,  etc.,  aid  in  determining  the  probable  difficulty  in 


THE  IRRIGATED  FARM  21 

securing  and  maintaining  proper  tilth.  The  depth  of  the  soil 
cither  to  hardpan  or  to  bedrock  should  be  determined,  as  upon 
this  depth  will  depend  to  some  extent  the  lasting  power  of  the 
soil.  The  natural  drainage  and  the  situation  of  the  land  with 
respect  to  probable  location  of  canals  and  other  irrigated  lands 
is  an  important  point.  It  is  a  fact  that  in  all  of  the  older  irri- 
gated sections,  some  of  the  lower  lying  lands  that  were  in  the 
early  days  most  productive  have,  with  the  development  of  irri- 
gation, become  water-logged  or  alkali-ridden.  Not  all  soils  are 
adapted  to  all  crops.  Some  soils  are  adapted  to  one  crop  but 
not  to  another.  This  is  illustrated  in  the  selection  of  soils  for 
peach  growing.  If  the  peach  tree  is  planted  upon  heavy  strong 
soils  or  soils  naturally  very  damp,  the  trees  will  grow  very  rapidly 
but  the  fruit  will  be  inferior  in  every  way.  Numerous  other 
illustrations  could  be  cited. 

6.  Soil  Moisture. — All  substances  contain  moisture  under 
normal  conditions.  Scientists  have  divided  all  moisture  con- 
tained with  the  soil  into  three  general  classes  with  respect  to  its 
physical  properties,  namely,  hygroscopic,  capillary  and  gravita- 
tional. Only  by  artificial  heating  can  soils  be  rendered  water- 
free. 

HYGROSCOPIC. — Water  which  in  nature  clings  to  all  matter, 
and  varies  in  amount  with  the  temperature,  dampness  of  the  air, 
sunshine,  and  other  less  important  factors,  is  called  hygroscopic. 
That  it  is  of  no  direct  value  to  plants  is  now  generally  conceded. 
According  to  Hilgard,  arid  region  soils  will  absorb  water  in  a 
saturated  atmosphere  equal  to  5.5  per  cent,  of  their  dry  weight. 
This  amount  represents  their  maximum  hygroscopic  capacity, 
but  the  actual  content  of  water  in  this  form  is  usually  much  less. 
Under  Great  Basin  conditions,  the  hygroscopic  content  is  reported 
by  Widtsoe  to  vary  from  0.75  to  3.50  per  cent.,  averaging 
approximately  1.5  per  cent. 

CAPILLARY. — Under  normal  field  conditions,  every  minute  soil 
particle  is  invested  with  a  very  thin  film  of  moisture.  Water 
thus  held  in  soils  is  called  capillary.  One  gram  of  a  coarse  sandy 
soil  according  to  Lyon  and  Fippin,  contains  3,276,000,000  par- 
ticles, while  the  same  weight  of  silt  loam  and  of  clay  soils  con- 
tain 9,639,000,000  and  19,525,000,000  particles  in  the  order 
named.  Provided  these  particles  were  spherical,  their  surface 


22  USE  OF  WATER  IN  IRRIGATION 

area,  in  square  feet  per  pound  of  soil  would  be  405,  1314,  and 
2000  respectively.  These  figures  clearly  indicate  how  soils  can 
contain  large  quantities  of  capillary  water,  even  though 
the  film  about  each  particle  is  very  thin. 

Moreover,  it  is  evident  that  as  the  soil  grains  decrease  in 
size,  and  the  number  and  surface  area  of  the  particles  per  unit 
of  volume  increase,  the  moisture  capacity  should  likewise  in- 
crease. This  is  in  fact  the  case.  Ordinary  plants  get  all  of 
their  water  from  the  capillary  form. 

GRAVITATIONAL. — Gravitational  water  or  that  which  percolates 
through  the  soil  due  to  the  force  of  gravity,  supplies  the  deficiency 
in  the  capillary  content  caused  by  plant  absorption  and  evapora- 
tion. Prof.  O.  W.  Israelsen  of  the  University  of  California 
states  that  "  irrigation  should  be  so  controlled  that  all  of  the 
gravitational  water  added  to  the  soil  will  be  changed  to  the 
capillary  form  before  it  is  lost  to  plants  by  passing  far  beyond 
their  root  zone  or  into  the  ground-water  table.  Each  farmer 
can,  by  the  use  of  a  soil  auger  make  enough  borings  after  ir- 
rigation to  determine  for  his  particular  soil  the  normal  depth 
of  penetration  of  a  given  amount  of  water  applied." 

The  relation  of  the  classes  of  soil  moisture  and  their  avail- 
ability to  plants  is  well  illustrated  in  the  following  diagram  after 
Lyon  and  Fippin. 

Hygroscopic  Capillary  Gravitational 


Unavailable  Available  Injurious 

FIG.  1. — Forms  and  relationship  of  soil  moisture. 

DETERMINING  SOIL  MOISTURE  CONTENT. — Soil  moisture,  or 
moisture  content  is  expressed  in  per  cents,  of  the  weight  of  dry 
soil.  This  is  determined  as  follows:  A  sample  of  wet  soil  is  dried 
in  an  oven  at  a  temperature  slightly  above  100  degrees  C.  or  212 
degrees  F.  until  no  further  loss  occurs  under  this  temperature. 
The  period  of  heating  required  is  dependent  upon  the  quality 
of  the  soil  and  the  wetness  of  the  sample  and  will  usually  take 


THE  IRRIGATED  FARM  23 

from  5  to  12  hours.     The  per  cent,  of  soil  moisture  or  moisture 

content  is  computed  thus: 

Loss  of  weight  in  drying 

—  =  Per  cent,  moisture  or  moisture  content. 
Weight  of  dry  soil  in  sample 

PROPER  PERCENTAGE  OF  SOIL  MOISTURE. — Irrigators  may  get 
a  general  knowledge  of  capillary  moisture  content  by  simply  air- 
drying  a  sample  of  soil  and  computing  percentage  as  above. 
Neither  method,  however,  gives  accurate  knowledge  of  the  water 
which  is  available  for  plants.  This  may  be  closely  approxi- 
mated by  deducting  from  the  per  cents,  obtained  by  the  method 
first  outlined,  the  per  cents,  at  which  ordinary  plants  wilt  in  soils 
of  the  class  tested.  The  " wilting  coefficient"  for  various  soils 
as  determined  by  Messrs.  Briggs  and  Shantz  are  quoted  below, 
but  it  should  be  remembered  that  under  normal  conditions, 
plants  can  derive  moisture  for  plant  growth  at  points  somewhat 
below  those  quoted  here.1 

Coarse  sand 0.9  Loam 13.1 

Fine  sand 3.2  Clay  loam ]  5 . 9 

Sandy  loam 7.0  Clay 25 . 2 

Fine  sandy  loam 10.7 

Lack  of  moisture  limits  plant  growth  over  about  65  per  cent, 
of  the  earth's  surface,  while  crop  production  is  also  prohibited 
on  large  areas  by  an  excess  of  water.  The  importance  of  an 
adequate  supply  of  moisture  and  the  bad  effects  of  too  much 
are  considered  in  other  parts  of  the  book.  It  is  apparent  that 
plants  differ  greatly  in  their  requirements  for  water.  These 
requirements  are  the  results  of  various  factors,  such  as  tem- 
perature, sunshine,  shade,  humidity,  and  the  plant  food  avail- 
able in  the  soil.  It  is  possible  for  man  to  exert  partial  control 
over  all  these  factors.  Soil  fertility,  however,  which  plays 
a  very  important  role  in  water  requirement  is  almost  entirely 
under  the  irrigator's  control.  If  farmers  desire  a  high  efficiency 
in  the  use  of  moisture,  they  must  maintain  an  adequate  supply 
of  plant  food  in  their  soils. 

Soils  should  not  be  too  wet  or  too  dry.  Either  extreme 
should  be  avoided  if  possible.  It  is  well  known  that  plants 

1  Bui.  230,  B.  P.  I.,     U.  S.  D.  A. 


24  USE  OF  WATER  IN  IRRIGATION 

which  are  grown  in  very  moist  soils  waste  water.  Moreover, 
evaporation  losses  from  such  soils  are  a  maximum.  Paradoxical 
as  it  may  seem,  plants  are  equally  wasteful  of  water  where  the 
moisture  content  of  the  soil  is  very  low.  Briggs  and  Shantz 
have  assembled  data  from  a  large  number  of  experiments  which 
indicate  that  the  water  requirements  for  every  pound  of  dry 
matter  produced  increase  as  either  extreme  in  moisture  content 
is  approached.  Such  relations  have  also  been  observed  in  the 
results  of  field  experiments  at  Davis,  California,  conducted  under 
the  auspices  of  the  Office  of  Experiment  Stations  in  cooperation 
with  the  State  Engineering  Department  and  the  University  of 
California.  Soils  which  are  kept  moist  absorb  water  much  more 
readily  than  those  which  have  been  allowed  to  become  very  dry 
and  in  very  dry  soils  bacteria  are  not  active.  It  is  important, 
therefore,  to  prevent  excessive  drying  out  in  order  to  allow 
plants  to  use  water  efficiently,  to  provide  for  continuous  plant 
food  formation  by  bacterial  action,  and  to  cause  water  to  be 
readily  absorbed. 

In  deep  loamy  soil,  according  to  Widtsoe,  a  total  moisture 
content  of  about  18  per  cent,  is  the  most  desirable  for  such 
crops  as  wheat,  oats,  barley,  alfalfa,  sugar  beets  and  potatoes. 
This  optimum  per  cent,  varies  with  the  soil,  decreasing  as  the 
soil  becomes  lighter  and  increasing  as  it  becomes  heavier.  The 
minimum  moisture  content  desirable,  varies  in  the  same  manner 
but  should  approximate  at  least  12  per  cent,  for  a  deep  loam. 

7.  Movement  of  Soil  Moisture. — The  forces  which  produce 
motion  in  the  water  of  soils  are  the  same  the  world  over.  It  is 
also  true  that  the  sources  from  which  the  water  is  derived  and 
the  manner  in  which  it  is  distributed  over  the  land  exert  an 
influence  in  the  direction  and  volume  of  subsurface  flow.  In 
a  humid  region  the  clouds  are  the  main  source  of  soil  water.  This 
falls  as  rain  or  snow  with  fair  uniformity  over  the  entire  surface. 
In  an  irrigated  district  with  its  light  rainfall  and  heavy  evapora- 
tion, the  main  source  of  water  is  the  artificial  canal  which  de- 
livers water  to  smaller  distributaries  on  benches  more  or  less 
distant  from  natural  streams.  A  large  part  of  the  water  so 
distributed  passes  under  the  forces  of  gravity  and  capillarity 
through  the  upper  stratum  of  soil  into  the  subsoil.  One  of  the 
first  effects  of  this  movement  of  water  is  to  raise  the  ground  water 


THE  IRRIGATED  FARM 


25 


level.  This  may  be  observed  by  noting  the  sudden  rise  of  water 
in  a  well  located  near  a  field  which  is  irrigated.  After  a  little 
time  the  greater  part  of  the  excess  water  which  caused  the  rise 
of  the  water  table  finds  its  way  through  the  subsoil  to  lower 
levels.  This  is  known  throughout  the  West  as  seepage  water. 

RATE  of  FLOW  of  SEEPAGE  WATER. — The  rate  of  flow  of  seepage 
and  underground  waters  generally  depends  upon  a  number  of 
conditions.  The  chief  of  these  are  (1)  the  available  head  or 
gradient,  (2)  the  relative  porosity  of  the  soil  and  (3)  the  tem- 
perature of  the  soil  and  water.  In  the  following  table,  compiled 
from  Water  Supply  Papers  Nos.  67  and  140,  U.  S.  Geological 
Survey  by  Prof.  Chas.  S.  Slichter,  the  velocity  of  flow  is  based  on 
a  fall  or  grade  of  100  feet  per  mile,  a  porosity  of  32  per  cent,  and 
a  temperature  of  50  degrees  F. 

TABLE  No.  8 


Kind  of  soil 

Diameter  of 
soil  grains, 
mm. 

Velocity 

In  feet  per 
day 

In  miles  per 
year 

Silt  
Verj  fine  sand 

0.01 
0.04 
0.05 
0.07 
0.09 
0.10 
0.15 
0.20 
0.25 
0.35 
0.45 
0.50 
0.65 
0.80 
0.95 
1.00 
3.00 
5.00 

0.0038 
0.0590 
0.0923 
0.1808 
0.2989 
0.3690 
0.8322 
1.476 
2.305 
4.520 
7.471 
9.224 
15.57 
23.62 
33.30 
36.90 
332.1 
1067.0 

0.00026 
'  0.00408 
0.00638 
0.01250 
0.02066 
0.02551 
0.05753 
0.1021 
0.1594 
0.3125 
0.5165 
0.6377 
1.077 
1.633 
2.302 
2.551 
22.96 
63.77 

Fine  sand 

Mediuni  sand                                   .  .  . 

Coarse  sand  

Fine  gravel  

CAPILLARY  MOVEMENT  of  SOIL  MOISTURE. — Capillary  movement 
may  be  readily  observed  in  furrow  irrigation  where  a  small  stream 
of  water  is  run  in  furrows  several  feet  apart.  If  the  flow  in  each 
furrow  were  not  acted  upon  by  any  force  other  than  gravity 
the  water  would  tend  to  sink  vertically  downward.  While 


26 


USE  OF  WATER  IN  IRRIGATION 


there  is  motion  in  this  direction  the  moisture  also  spreads  side- 
wise  so  as  to  moisten  in  time  all  the  intervening  space  between 
the  furrows.  In  the  case  of  deep  furrows,  such  as  are  used  in 
the  irrigation  of  potatoes,  the  water  is  not  only  drawn  sidewise 
but  upward,  thus  overcoming  the  pull  of  gravity. 

The  action  of  this  natural  force  is  of  paramount  importance  to 
agriculturists  in  general,  and  especially  to  irrigators.  The  latter 
have  to  devise  ways  and  means  to  moisten  the  soil  artificially  and 
without  the  aid  of  this  force  it  would  be  impossible  to  distribute 
water  in  soils  so  effectively  or  to  maintain  the  proper  amount  of 
moisture  within  the  root  zone  of  plants.  Thus,  when  a  relatively 
dry  soil  lies  next  to  a  wet  soil  the  excess  of  film  water  in  the 
latter  is  gradually  drawn  to  the  former.  Again,  when  the  root- 
lets of  a  plant  absorb  the  moisture  in  the  soil  around  them  the 
deficiency  is  made  up  by  drawing  moisture  from  wet  soils. 
So,  too,  as  the  top  layer  of  soil  is  robbed  of  its  moisture  by  evapora- 
tion, a  fresh  supply  is  raised  from  below.  Hence  it  is  apparent 
that  this  force  not  only  aids  the  irrigator  to  distribute  water  in 
soils  but  acts  as  a  great  equalizer  of  soil  moisture. 

Capillary  force  or  surface  tension  as  it  is  sometimes  called,  is 
usually  compared  and  measured  by  placing  the  lower  ends  of 
columns  of  typical  soils  or  soil  ingredients  in  contact  with 
water  and  noting  the  vertical  height  to  which  water  will  rise 
through  the  material  in  a  given  time.  The  movement  of  soil 
moisture  due  to  this  force  may  be  measured  by  determining  the 
amount  of  water  which  is  raised,  say  a  foot  high,  through  the 
material  in  a  given  time.  When  the  lower  end  of  a  column  of 
air-dry  soil  is  brought  into  contact  with  water,  the  rise  of  the 
water  in  the  soil  is  at  first  quite  rapid.  This  is  seen  in  Table  9. 
After  the  end  of  the  first  day  or  so  the  rise  is  less  rapid  as  is 
shown  in  Table  10,  and  in  time  reaches  a  height  beyond  which 
it  does  not  rise. 

TABLE  No.  9 
Capillary  Rise  of  Moisture  in  Soils.     (Hilgard) 


of  soil 


Clay 


Silt 


Medium  sand      Sandy  loam 


Rise  of  moisture  

Inches 

Inches 

Inches 

Inches 

End  of  1  hour  

0.5 

11 

10 

7 

End  of  1  day  

2.0 

43 

13 

17 

End  of  6  days 

8  0 

65 

22 

23 

End  of  10  days  

13.0 

72 

23 

25 

THE  IRRIGATED  FARM 


27 


TABLE  No.  10 

Height  of  Rise  of  Water  in  Dry  Soils  of  Different  Texture. 

Pippin) 


(Lyon  and 


Time 

Min. 

Hours 

Days 

15 

1      |      2 

| 

3        |      8            13 

10 

Silt  and  very  fine  sand  . 
Very  fine  sand  
Fine  sand 

In. 

2.7 
7.6 
9.0 

5.8 
4.0 

In. 

4.7 
10.0 
9.5 

6.0 
5.0 

In. 
7.0 
12.4 
10.0 

6.3 
5.3 

In. 

20.0 
21.0 
11.6 

7.5 
6.4 

In. 
30.0 
23.0 
13.0 

9.0 
8.0 

In. 

45.0 
26.0 
14.3 

10.0 
9.0 

In. 

52.0 
27.5 
15.2 

11.5 

10.0 

In. 

56.0 
28.5 
16.0 

12.5 

10.8 

Coarse     and     medium 
sand  
Fine  gravel  

CHAPTER  III 
THE  NECESSARY  EQUIPMENT  AND  STRUCTURES 

8.  Equipment  for  the  New  Settler. — Many  advertisements 
for  the  sale  of  irrigated  lands  state  or  leave  the  impression  that 
men  with  but  little  capital  and  experience  can  easily  make  a 
success  upon  such  lands.  While  it  is  true  that  the  ability  to  do 
hard  work,  a  willingness  to  suffer  privations  and  a  determina- 
tion to  succeed  greatly  supplement  a  small  bank  account,  yet 
there  are  many  demands  for  capital  which  must  be  met.  Before 
purchasing,  the  prospective  settler  should  either  have  sufficient 
money  to  meet  such  demands  or  know  from  whence  he  may 
secure  it  when  needed. 

The  first  expenditure  required  of  the  prospective  settler  is 
the  first  payment  upon  the  land.  This  varies  in  price  accord- 
ing to  locality  and  the  cost  of  developing  the  project.  Prior 
to  moving  to  the  land  a  house  should  be  built  for  habitation. 
The  settler  may  provide  a  temporary  structure  but  this  should 
be  fairly  well  built  since  it  may  have  to  do  service  for  several 
years.  The  size  and  cost  of  such  a  house  and  its  furnishings 
will  depend  to  a  large  extent  upon  the  size  of  the  family.  In 
addition  a  barn  will  be  required  for  whatever  live  stock  is  pur- 
chased. The  settler  should  provide  himself  with  a  good  team 
and  wagon  complete  with  harness,  an  extra  horse,  a  milch  cow, 
two  pigs  and  fowls. 

For  reclaiming,  leveling  and  putting  the  land  under  cultiva- 
tion a  plow,  harrow,  leveller  and  other  implements  will  be  re- 
quired. While  not  absolutely  necessary  the  settler  will  find 
that  the  purchase  of  a  few  miscellaneous  tools  for  working  in 
wood  and  metal  will  prove  a  great  convenience.  Some  imple- 
ments, such  as  a  mower  and  hay  rake  can,  no  doubt,  be  rented 
from  some  neighbor  whenever  needed. 

Fencing  the  entire  place  may  be  out  of  the  question  for  the 
first  year  or  two  but  should  be  done  as  soon  as  practicable 

28 


NECESSARY    EQUIPMENT    AND    STRUCTURES  29 

in  order  to  furnish  pasturage  for  the  cow  thus  reducing  the 
feed  bill  to  some  extent.  At  any  rate  enough  fencing  should 
be  provided  to  build  a  feed  coral  at  the  barn. 

The  settler  should  move  to  the  farm  some  time  during  the  fall 
or  early  spring,  preferably  the  latter,  before  the  cropping  season 
begins  in  order  to  clear,  plow  and  level  a  portion  of  the  land 
for  cultivation.  This  tilling  of  the  soil  will  involve  the  purchase 
of  seed  and  the  yields  for  the  first  year  will  barely  pay  expenses 
of  cropping  and  in  many  cases  barely  furnish  enough  seed  for 
the  increased  acreage  the  following  season.  As  the  returns 
from  the  first  season  will  be  light  the  settler  must  provide  pro- 
visions for  himself  and  family  and  feed  for  the  live  stock  dur- 
ing the  first  season  and  the  greater  portion  of  the  following 
season. 

It  is  very  doubtful  whether  the  return  from  the  crops  will 
furnish  a  living  to  the  settler  and  meet  the  expenses  incurred 
by  such  improvements  as  will  be  required  from  time  to  time 
within  several  years.  Usually  on  most  projects  the  second 
payment  with  deferred  interest  falls  due  at  the  end  of  the 
first  season  and  this  money  must  be  derived  from  outside 
sources. 

At  some  certain  date  during  the  year,  fixed  by  statute,  the 
settler  becomes  subject  to  taxation  for  both  personal  property 
and  real  estate.  Lands  located  upon  Carey  Act  projects 
become  taxable  as  soon  as  final  proof  is  made,  while  those 
located  upon  Reclamation  projects  of  the  United  States  are 
not  taxed  until  title  is  obtained.  Assessments  to  provide  for 
maintenance  and  operation  charges  for  irrigation  works  must, 
of  course,  be  met  each  year  whether  the  land  is  patented 
or  not. 

No  title  to  the  land  can  be  acquired  until  all  payments  have 
been  made.  As  only  equity  to  the  land  can  be  given  as  security 
for  loans  interest  becomes  high  and  credit  limited  making  loans 
on  real  estate  held  in  equity  hard  to  float.  Thus  payments 
with  deferred  interest  can  not  be  raised  by  making  loans  on 
the  place  but  must  be  derived  from  outside  sources  until  such 
time  as  the  farm  has  reached  a  paying  basis. 

Summarizing,  the  settler  will  require  money  to  meet  the 
following  expenditures : 


30  USE  OF  WATER  IN  IRRIGATION 

First  payment  on  the  land.  Two  pigs. 

House.  Fowls. 

Domestic  water  supply.  Plow. 

Barn.  Land  leveler. 

Two  or  three  horses  with  wagon.  Harrow. 

Milch  cow.  Miscellaneous  tools. 

Taxes — personal  and  real  estate. 

Fencing — at  least  enough  for  corral. 

Provisions  for  two  seasons. 

Feed  for  live  stock  for  greater  portion  of  two  seasons. 

Seed  for  seeding  land. 

Annual  payments  and  deferred  interest  until  farm  reaches  paying 
basis. 

All  of  the  above  expenditures  involve  a  supply  of  ready  cash 
which  can  be  drawn  upon  as  needed.  Due  to  the  range  of 
prices  in  the  local  markets  throughout  the  different  sections 
of  the  country  the  amount  of  available  money  required  will  vary 
for  the  various  sections.  H.  C.  Diesem,  Irrigation  Engineer 
of  the  Department  of  Agriculture,  who  has  had  a  varied  ex- 
perience in  dealing  with  new  settlers  believes  that  a  prospective 
settler  going  upon  a  40-acre  farm  in  a  newly  developed  section 
should  have  an  available  fund  of  from  $1500  to  $3000  with 
which  to  meet  expenses  as  they  may  arise. 

9.  Laying  Out  a  Farm  under  an  Irrigation  System. — "The 
governing  factor  in  laying  out  a  farm  which  is  to  be  irrigated" 
according  to  F.  L.  Bixby,  Irrigation  Engineer  of  New  Mexico, 
"  consists  in  providing  proper  facilities  for  the  ready  and  uniform 
distribution  of  water  to  all  parts."  Since  the  location  and  cost 
of  permanent  farm  ditches  depend  to  a  large  degree  on  surface 
configuration,  it  is  a  saving  of  money  in  the  end  to  have  a  survey 
and  topographic  map  made  of  the  entire  tract.  If  this  can  not 
be  done  surface  levels  should  be  taken  to  fix  the  proper  loca- 
tion of  the  fields,  ditches,  and  other  permanent  features.  The 
supply  ditch  from  the  main  canal  or  from  one  of  its  branches 
should  be  as  short  and  as  large  as  possible.  The  main  points 
to  be  kept  in  mind  in  fixing  its  location  are  to  convey  the  water 
with  the  least  loss  to  the  highest  part  of  the  farm  if  practicable, 
to  run  parallel  to  fence  lines  or  field  borders,  to  avoid  use  of 
syphons,  flumes  or  dikes  and  to  adopt  a  suitable  grade.  The 
capacity  of  the  supply  ditch,  as  well  as  the  capacity  and  direction 


NECESSARY    EQUIPMENT    AND    STRUCTURES  31 

of  the  farm  ditches,  depend  on  the  size  of  the  farm  and  fields, 
the  method  to  be  followed  in  irrigating,  the  kind  of  crops  which 
are  likely  to  be  raised  and  other  considerations. 

Owing  to  the  nature  of  land  surveys,  irrigated  farms  usually 
comprise  some  even  multiple  of  the  10-acre  tract.  This  unit 
also  forms  a  convenient  size  for  fields  where  the  topography  will 
admit  of  such  an  arrangement.  If  too  large  for  a  field,  a  10- 
acre  tract  can  be  subdivided  in  the  direction  in  which  it  is  ir- 
rigated. The  width  or  length  (660  feet)  of  this  unit  of  area 
is  about  as  long  a  distance  as  water  should  be  run  in  furrows. 
In  laying  out  small  tracts  of  land  for  suburban  settlers  in  ir- 
rigated districts  the  rectangular  form  has  some  advantages. 
Dr.  H.  C.  Gardiner  of  the  Anaconda  Copper  Mining  Company, 
in  subdividing  lands  for  this  class  of  occupants  on  the  outskirts 
of  Anaconda,  adopted  the  arrangement  shown  in  Fig.  2.  This 


6U 


10  Acres 


1000' 


-20' 


10  Acres 


1000' 


FIG.  2. — Arrangement  of  tracts  for  suburban  irrigated  farms. 

lessens  the  number  of  roads  or  streets,  facilitates  the  distribution 
of  water,  is  better  adapted  to  the  rotation  of  crops  and  removes 
to  a  greater  distance  from  the  residence  the  ugly  and  unwhole- 
some features  of  farm  life. 

In  laying  out  fields  and  permanent  farm  ditches,  one  should 
not  overlook  crop  rotation.  The  same  field  may  be  in  root 
crops  one  season,  in  cereals  the  next  and  in  a  legume  the  third. 
With  the  exception  of  fruits,  vines,  and  a  few  other  crops,  rota- 
tion of  one  kind  or  another  is  quite  generally  practised  under 
irrigation  and  it  is  well  to  plan  farms  at  the  start  so  as  to  con- 
form to  this  use.  Owing  to  the  wide  variation  of  soils  on  some 
farms  and  to  the  further  fact  that  particular  soils  are  adapted 
to  particular  crops,  it  is  well  to  set  aside  a  certain  field  for  a 
special  crop,  such  as  fruit  trees.  The  Director  of  the  state  ex- 
periment station  in  which  the  farm  is  located  may  be  with  profit 
consulted  on  matters  pertaining  to  soils,  crops  and  climate. 


32  USE  OF  WATER  IN  IRRIGATION 

FARM  BUILDINGS. — Good  drainage  and  sanitation  are  prime 
requisites  in  fixing  the  location  of  a  farm  home.  Such  questions 
as  facing  the  public  highway,  exposure  to  high  or  chilling  winds,  the 
advantage  of  a  beautiful  outlook  and  accessibility  to  other  parts 
of  the  farm,  although  of  much  importance  in  themselves,  occupy 
a  second  place.  Sometimes  a  part  of  the  farm  is  too  high  to  be 
watered  by  a  gravity  ditch  and  this  cheap  and  dry  part  may  be 
utilized  for  farm  buildings  and  yards.  This  proves  a  good 
selection  providing  water  can  be  pumped  or  otherwise  secured 
for  domestic,  lawn  and  garden  purposes.  Farm  houses  should  be 
set  back  at  least  100  feet  from  roads  or  bare  ground  to  avoid 
the  discomfort  of  drifting  dust  and  to  assure  an  attractive  setting 
of  lawn  and  shrubbery.  Whatever  the  source  of  the  domestic 
water  supply,  whether  from  a  well,  cistern  or  spring,  it  should 
be  carefully  guarded  from  contamination.  A  water-tight  cess- 
pool or  septic  tank  should  be  provided  but  if  this  can  not  be 
built  great  care  should  be  used  to  protect  sewage  from  flies  and 
to  convey  it  beyond  the  possible  reach  of  the  water  supply 
through  surface  channels  or  underground  percolation.  This 
highly  important  feature  is  commonly  overlooked  as  may  be 
seen  in  the  careless  location  of  sewage  drains  and  outbuildings. 
Its  careful  observance  is  an  excellent  preventative  of  typhoid  and 
similar  diseases.  The  homestead  should  likewise  be  protected 
from  prevailing  winds  by  a  grove  of  trees  of  the  variety  best 
suited  to  the  climate  and  soil.  Poplar  or  cottonwood,  and  in 
localities  of  little  frost,  eucalyptus,  when  well  watered,  will  grow 
rapidly.  These  may  alternate  with  the  slow-growing  elms, 
box  elders,  oaks  and  peppers.  Good  roads  and  lanes  lined  with 
shade  trees,  not  only  enhance  the  value  of  the  farmstead  but 
add  greatly  to  its  attractiveness.  The  farm  home  and  its  sur- 
roundings in  an  irrigated  district  need  not  be  expensive  in  order 
to  be  beautiful.  Where  there  is  an  abundance  of  rich  soil,  a 
ready  supply  of  water  and  a  favorable  climate,  it  is  easy  to  con- 
vert a  dreary  abode  into  an  attractive  residence.  Green  grass 
soon  covers  the  drifting  sands,  a  climbing  rose  or  a  vine  conceals 
an  ugly  exterior  and  the  foliage  of  shrubs  and  trees  affords  shelter 
from  the  rays  of  the  western  sun. 

10.  Farm  Ditches. — Farm  ditches  are  either  permanent  or 
temporary.  The  former  include  the  main  supply  ditch  to  the 


NECESSARY    EQUIPMENT    AND    STRUCTURES  33 

farm  and  its  various  branches  to  subdivisions  of  the  farm.  The 
latter  are  confined  to  the  small  distributaries  in  each  field  and 
are  renewed  for  each  crop. 

LOCATION. — The  chief  features  to  be  considered  in  locating 
permanent  farm  ditches  were  pointed  out  in  Art.  9.  It 
may  be  stated  here  by  way  of  emphasis  that  too  much  care  can 
not  well  be  given  to  this  subject  since  faults  of  location  in  such 
channels  affect  the  whole  farm.  The  most  common  mistake 
made  by  farmers  is  to  lay  out  and  build  a  system  of  ditches  for 
a  part  of  the  farm  without  regard  to  the  irrigation  of  the  re- 
mainder. Since  these  are  considered  temporary  in  character 
little  attention  is  paid  to  them  but  after  the  lapse  of  years  it  is 
found  both  difficult  and  costly  to  abandon  the  old  and  begin 
anew. 

GRADE  OF  DITCHES. — The  quantity  of  water  which  a  ditch  will 
carry  depends  fully  as  much  on  the  fall  or  grade  as  on  its  size. 
The  two  elements  should  be  considered  together.  When  con- 
ditions are  such  that  one  can  adopt  a  suitable  grade  the  chief 
points  to  consider  are  the  volume  to  be  carried  and  the  nature 
of  the  soil.  The  smaller  the  volume  the  greater  the  grade 
required.  In  a  small  ditch  capable  of  carrying  50  miner's  inches 
a  fall  of  2  inches  to  the  rod  would  produce  a  velocity  of  2  feet  per 
second,  while  in  a  ditch  capable  of  carrying  950  miner's  inches 
the  fall  required  to  give  the  same  velocity  is  only  1/4 
inch  to  the  rod.  In  fine  sand  or  sediment  a  flat  grade  is  required 
to  prevent  scouring.  A  mean  velocity  of  1  foot  per  second  is 
sufficient  for  such  material.  In  hard  gravel  or  hard  clay  or  in 
a  mixture  of  these,  a  velocity  of  3  feet  per  second  can  be  used 
without  eroding  the  bottom.  In  ordinary  materials,  ranging 
from  sandy  or  gravelly  loams  to  clay  loams,  a  grade  may  safely 
be  adopted  which  will  produce  a  mean  velocity  of  2  to  2  1/2  feet 
per  second.  On  a  farm  with  little  fall  the  grade  can  not  exceed 
that  of  the  land.  On  rolling  land  or  where  the  slope  is  steep  a 
suitable  grade  for  ditches  can  usually  be  found  by  running  them 
across  the  slopes  rather  than  directly  down  them.  When  ex- 
cessive grades  can  not  be  avoided  by  winding  around  the  high 
places  the  speed  of  the  water  may  be  checked  at  intervals  by 
the  insertion  of  drops  or  a  rough  pavement  of  cobble  stones 
loosely  laid.  Check  boards  are  convenient  to  direct  water  into 


34 


USE  OF  WATER  IN  IRRIGATION 


laterals,  and  at  a  slight  additional  expense  they  may  be  com- 
bined with  a  permanent  drop.  Considering  the  ditch  alone  it 
is  preferable  to  use  a  grade  which  for  its  size  will  give  a  velocity 
just  safely  less  than  will  cause  cutting  in  the  type  of  soil  through 
which  it  is  to  be  built. 


Farm  Ditch  No.  2 

*^%& 


Farm  Ditch  No.l 


•:•'£•£>•• 

Farm  Ditch  No.  3 


Farm  Ditch  No.4  when  New 


Original 


Farm  Ditch  No.4  after  being  used 
"Water  Level 

Farm  Ditch  No.  5  when  New 
"Water  Level 


K— -3— 


Farm  Ditch  No.5  after  being  used 

FIG.  3. — Farm  ditches  of  various  capacities. 

FORM  OP  DITCHES. — The  principal  function  of  both  the  per- 
manent and  temporary  ditches  is  to  get  water  on  the  land  quickly 
and  easily.  To  do  this  the  form  of  the  ditch  should  be  such  that 
the  water  surface  in  the  ditch  is  kept  above  the  ground  to  be 


NECESSARY    EQUIPMENT    AND    STRUCTURES  35 

covered.  Ditches  should  not  be  allowed  to  cut  deeply  into  the 
ground  so  that  diversion  is  hindered.  When  being  built  they 
should  be  well  banked  so  that  the  turnouts  can  be  made  without 
having  to  raise  the  water  above  safe  limits  on  the  banks  above. 
The  form  of  the  cross  section  of  a  ditch  depends  largely  on  its 
method  of  construction.  Small  ditches  made  with  a  V  crowder 
(Fig.  5),  are  generally  triangular  in  shape  when  built.  If  the 
velocity  is  not  such  that  scour  will  occur  these  usually  become 
rounded  as  shown  in  Ditches  Nos.  4  and  5  (Fig.  3). 

The  larger  ditches  are  usually  constructed  with  a  scraper 
working  across  from  side  to  side  making  a  bank  on  both  sides  in 
nearly  level  ground  and  on  only  the  lower  side  in  side-hill  work. 
Such  ditches  are  best  built  with  curved  cross  section  as  the 
squaring  to  a  regular  trapezoidal  shape  does  not  give  advan- 
tages in  proportion  to  the  work  required.  In  ditches  made 
wide  enough  for  a  slip  or  scraper  to  be  run  along  in  the  direction 
of  the  length  of  the  ditch,  the  trapezoidal  shape  is  as  easily 
built  as  the  curved.  Typical  shapes  and  dimensions  for  small 


FIG.  4. — Home-made  level  for  locating  ditches. 

ditches  are  shown  in  the  accompanying  cuts,  the  ditches  shown 
being  those  for  which  the  tables  of  capacity  given  later  are 
computed. 

CAPACITY. — The  capacity  needed  depends  chiefly  on  the  manner 
of  delivering  the  water  and  the  methods  used  in  applying  it.  It 
also  depends,  but  to  a  less  extent,  on  the  size  of  the  farm,  the 
duty  of  water,  the  nature  of  the  soil  and  the  crops  raised. 

FLOW  OF  WATER  IN  FARM  DITCHES. — In  the  table  which  follows 
(Table  No.  11)  the  flow  in  each  of  the  five  types  of  farm  ditches 
previously  shown  (Fig.  3)  has  been  figured  for  different 
grades.  These  grades  are  intended  to  cover  ordinary  conditions 
on  most  farms  and  are  expressed  in  three  ways :  First,  in  inches 
and  fractions  of  an  inch  per  rod;  next  in  feet  per  100  feet;  and, 
lastly,  in  feet  per  mile.  The  mean  or  average  velocity  of  the 


36 


USE  OF  WATER  IN  IRRIGATION 


water  in  each  kind  of  ditch  having  a  given  grade  is  also  given, 
as  well  as  the  discharge  in  cubic  feet  per  second  and  its  equiva- 
lent in  miner's  inches  under  a  6-inch  pressure  head,  about  40 
of  such  inches  being  equal  to  1  cubic  foot  per  second.  Thus  in 
farm  ditch  No.  3  a  grade  of  1/2  inch  per  rod  produces  a  dis- 
charge of  168  miner's  inches,  but  when  the  grade  is  increased  to 
3/4  inch  per  rod  the  discharge  is  207  miner's  inches. 


TABLE  No.  11 

Table  giving  the  Mean  Velocity  and  Discharge  of  Ditches- with  Different 
Grades.     Lateral  ditch  with  bottom  width  of  14  inches    (ditch   No.  1) 


Grade 

Mean  velocity 
in    feet    per 
second 

Discharge 

Inches 
per  rod 

Feet  per 
100  feet 

Feet  per  mile 

Cubic  feet  per 
second 

Miner's  inches 
under  6-inch 
pressure  head 

1/2 

0.25 

13.33 

1.01 

0.67 

27 

3/4 

0.38 

20.00 

1.23 

0.81 

32 

1 

0.51 

26.67 

1.42 

0.93 

37 

11/4 

0.63 

33.33 

1.59 

1.05 

42 

11/2 

0.76 

40.00 

1.75 

1.16 

46 

2 

1.01 

53.33 

2.04 

1.35 

54 

21/2 

1.26 

66.67 

2.28 

1.50 

60 

3 

1.51 

80.00 

2.50 

1.64 

66 

31/2 

1.77 

93.33 

2.70 

1.78 

71 

Lateral  ditch  with  bottom  width  of  16  inches  (ditch  No.  2) 


1/4 

0.13 

6.67 

0.82 

0.80 

30 

1/2 

0.25 

13.33 

1.16 

1.00 

42 

3/4 

0.38 

20.00 

1.42 

1.30 

52 

1 

0.51 

26.67 

1.64 

1.50 

60 

1  1/4 

0.63 

33.33 

1.84 

1.70 

67 

11/2 

0.76 

40.00 

2.02 

1.80 

74 

13/4 

0.88 

46.67 

2.18 

2.00 

80 

2 

1.01 

53.33 

2.34 

2.10 

86 

21/2 

1.26 

66.67 

2.61 

2.40 

96 

Lateral  ditch  with  bottom  width  of  2  feet  (ditch  No.  3) 


1/8 

0.06 

3.33 

0.79 

2.08 

83 

1/4 

0.13 

6.67 

1.13 

3.00 

119 

1/2 

0.25 

13.33 

1.60 

4.20 

168 

3/4 

0.38 

20.00 

1.97 

5.20 

207 

1 

0.51 

26.67 

2.28 

6.00 

239 

1  1/4 

0.63 

33.33 

2.57 

6.80 

270 

NECESSARY    EQUIPMENT    AND    STRUCTURES  37 


TABLE  No.  11     (Continued) 

Table  giving  the  Mean  Velocity  and  Discharge  of  Ditches  with  Different 
Grades.    Lateral  ditch  with  bottom  width  of  4  feet  (ditch  No.  4) 


Grade 

Discharge 

Inches 
per  rod 

Feet  per 
100  feet 

Feet  per  mile 

in  feet  per 
second 

Cubic  feet  per 
second 

Miner's  inches 
under  6-inch 

pressure  head 

1/16 

0.03. 

1.58 

0.84 

4.20 

168 

1/8 

0.06 

3.33 

1.08 

5.40 

216 

1/4 

0.13 

6.67 

1.54 

7.70 

308 

3/8 

0.19 

10.00 

1.89 

9.50 

378 

1/2 

0.25 

13.33 

2.20 

11.00 

440 

5/8 

0.31 

16.67 

2.45 

12.20 

490 

3/4 

0.38 

20.00 

2.69 

13.40 

538 

Lateral  ditch  with  bottom  width  of  6  feet  (ditch  No.  5) 


1/16 

0.03 

1.67 

1.03 

11.6 

464 

1/8 

0.06 

3.33 

1.48 

16.7 

666 

3/16 

0.09 

5.00 

1.82 

20.5 

819 

1/4 

0.13 

6.67 

2.11 

23.7 

950 

5/16 

0.16 

8.33 

2.35 

26.4 

1,058 

3/8 

0.19 

10.00 

2.58 

28.0 

1.121 

7/16 

0.22 

11.67 

2.80 

30.5 

1,260 

INSTRUMENTS  NEEDED  IN  LAYING  OUT  DITCHES. — In  laying 
out  supply  ditches  an  engineer's  level  and  rod  are  the  most  con- 
venient instruments.  The  distances  may  be  estimated  by 


Old  Wagon  liref 

FIG.  5. — V-crowders  used  in  building  farm  ditches. 

pacing.  When  such  instruments  are  not  available,  a  useful 
substitute  consists  of  an  ordinary  carpenter's  spirit  level  attached 
to  a  portable  wooden  frame,  a  sketch  of  which  is  shown  in  Fig. 
4.  When  first  made  and  placed  on  a  level  surface  the  bubble 
should  come  to  the  center  of  its  run.  Then  one  leg  is  short- 
ened by  the  amount  of  the  grade  per  rod  (see  Table  of  Grades). 


38  USE  OF  WATER  IN  IRRIGATION 

The  device  is  operated  by  one  man,  who  first  places  the  shorter 
leg  at  the  surface  of  the  water  in  the  main  canal  or  supply  ditch 
and  swings  the  other  end  around  until  the  bubble  conies  to  the 
center.  The  location  of  the  longer  leg  is  then  marked  by  a 
helper,  who  carries  a  shovel  and  removes  part  of  a  shovelful  of 
earth.  The  level  is  then  carried  forward  until  the  shorter  leg 
occupies  the  position  vacated  by  its  mate,  when  a  second  mark  is 
made.  This  operation  is  repeated  until  the  line  is  laid  out  and  a 
furrow  is  run  connecting  all  of  the  temporary  marks. 


FIG.  6. — Wing  plow. 

CONSTRUCTION. — Usually  for  the  construction  of  farm  ditches 
the  ground  is  plowed  to  the  width  desired.  With  small  ditches 
a  lister  or  ditch  plow  may  be  run  through  once  and  the  ditch 
shaped  by  hand  or  with  a  small  log  crowder.  With  larger 
ditches  as  many  furrows  as  needed  can  be  plowed  and  a  V  crowder 
such  as  is  shown  in  Fig.  5  used  to  shape  the  ditch  and  pile  the 
earth  in  the  banks.  By  varying  the  shape  of  the  V  or  by  the 
driver  and  helper  shifting  their  weight  in  riding  the  crowder,  the 
ditch  can  be  shaped  to  almost  any  desired  form.  A  wing  plow 
such  as  is  shown  in  Fig.  6  can  be  used  to  plow  and  clean  the 
ditch  at  the  same  time.  For  larger  ditches  graders  can  be  used. 
A  greater  range  of  adjustment  of  the  blade  is  needed  for  ditch 
work  than  for  leveling. 

In  case  it  is  necessary  to  build  the  ditch  in  fill  over  low  places, 
the  necessary  dirt  for  the  fill  can  be  brought  from  the  adjoining 
ground  and  the  ditch  shaped  on  its  top  as  in  level  ground. 

If  possible  ditches  should  be  built  some  time  before  use  so 
that  the  banks  may  have  time  to  settle.  In  case  the  banks 
are  still  soft  when  water  is  first  run  great  care  should  be  taken  to 
avoid  breaks. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  39 

MAINTENANCE.1 — Maintenance  of  farm  ditches  aside  from  the 
repairs  to  structure  is  principally  of  two  kinds,  the  prevention 
or  removal  of  weeds  and  the  cleaning  out  of  silt  and  aquatic 
growths.  In  the  case  of  weeds,  prevention  where  practicable  is 
preferable.  Irrigation  waters  usually  carry  weed  seeds.  If  the 
grade  of  the  farm  ditch  is  such  as  to  give  as  high  a  velocity  as  in 
the  lateral  from  which  the  water  is  received,  the  weed  seed  and 
silt  can  be  largely  carried  on  through  to  the  fields.  More  trouble 
is  generally  experienced  from  weeds  on  ditches  with  low  velocities. 
The  planting  of  alfalfa  or  other  crops  on  the  ditch  banks  is  a 
preventive  measure.  The  cutting  of  weeds  before  they  seed 
at  slack  times  is  another.  In  some  cases  aquatic  growths  occur 
which  reduce  the  carrying  capacity  to  such  a  degree  that  irriga- 
tion must  be  stopped  and  the  ditch  cleaned.  These  growths  may 
be  grass  growing  in  the  water  or  on  the  banks  and  drooping  over 
into  the  ditch  or  they  may  be  trailing  moss,  water  cress,  or  other 
forms  of  water  plants.  In  ditches  in  use  only  a  part  of  the  time 
the  moss  is  usually  killed  during  the  periods  the  ditch  is  dry. 
The  grasses,  however,  grow  best  at  such  times  in  the  wet  mud  of 
the  ditch  bottom.  In  farm  ditches  the  grasses  can  be  mowed 
with  a  hand  scythe  without  having  to  shut  off  the  water.  Regu- 
lar and  smooth  banks  will  allow  the  use  of  the  mowing  machine 
for  a  large  part  of  the  weeds  and  grass  leaving  only  the  finishing 
for  the  scythe.  The  cleaning  of  ditches  is  generally  a  neces- 
sity in  the  spring  whether  the  ditch  is  one  that  scours  or  one 
that  silts.  In  a  ditch  which  scours,  the  undercut  banks  will 
need  shaping.  In  a  ditch  which  silts,  the  deposits  will  need  to 
be  removed.  This  may  be  done  either  by  hand  shoveling  where 
small  in  amount  or  by  any  of  the  methods  described  for  the 
original  construction. 

11.  Irrigation  Structures  for  the  Farm. — The  structures  which 
may  be  used  on  an  irrigated  farm  in  connection  with  the  use  of 
water  include  headgates,  measuring  devices,  flumes,  pipes,  cul- 
verts, wells,  cisterns,  reservoirs,  etc.  Many  of  these  have 
been  described  under  other  headings  and  need  not  be  considered 
here. 

1  On  this  subject  as  well  as  that  of  farm  ditches  in  general  the  writer 
has  drawn  from  the  experience  of  S.  T.  Harding  of  the  University  of 
California. 


40 


USE  OF  WATER  IN  IRRIGATION 


DELIVERY  GATES. — A  headgate  is  needed  to  control  the  flow  from 
the  main  or  branch  canal  into  a  private  ditch.  The  gate  and  its 
framework,  together  with  the  pipe  or  box  which  conducts  the 
water  out  of  the  canal  into  the  farmer's  ditch  is  sometimes 
termed  a  turnout.  A  structure  of  this  kind  should  meet  the 
requirements  of  both  the  canal  company  and  the  water  user. 
The  interests  of  the  water  company  demand  that  it  be  secure, 
water-tight  when  closed,  large  enough  to  admit  the  necessary 


Gate  Partly  Open  and 

FIG.  7. — Delivery  gate  to  farm  lateral. 


flow  and  so  designed  that  it  will  not  discharge  after  adjustment 
more  than  a  certain  fixed  quantity  of  water.  The  water  user 
is  likewise  interested  in  having  a  substantial  structure  of  ample 
size  but  in  addition  he  desires  it  to  be  designed  in  such  a  way  that 
he  can,  when  he  chooses,  close  it  partly  or  altogether.  The 
wooden  headgate,  Fig.  7,  designed  by  F.  C.  Scobey,  is  intended 
to  be  connected  with  a  wooden  box  or  flume. 

Another  type  of  wooden  headgate  with  screw  lift  designed  by 


NECESSARY    EQUIPMENT    AND    STRUCTURES  41 


FIG.  8. — Another  type  of  wooden  gate. 


FIG.  9. — Metal  delivery  gate  and  frame. 


42 


USE  OF  WATER  IN  IRRIGATION 


J.  L.  Rhead  and  used  by  the  writer  on  the  Bear  River  Canal 
laterals  is  shown  in  Fig.  8. 

A  more  durable  delivery  gate  made  by  the  Kellar-Thomasoii 
Mfg.  Co.,  of  Los  Angeles,  Cal.,  consists  of  a  metal  gate  and 
frame  attached  to  a  short  line  of  pipe  laid  beneath  the  canal 
bank.  The  pipe  may  be  vitrified  clay,  concrete  or  steel.  Fig. 
9  shows  a  connection  made  with  a  steel  pipe. 

One  of  the  latest  types  of  delivery  gates  in  use  in  the  Imperial 
Valley,  California,  for  admitting  water  to  borders  is  made  by 
moulding  a  concrete  head  on  a  joint  of  concrete  pipe  the  open- 
ing being  regulated  by  a  galvanized  iron  gate  held  in  place  by 


.i. 


%;_ 

,  ^jj-^--'--^--''-0"  '•' :'" !  -'-"•-  '•'-'- 


24- 

Concrete  Pipe 


Front  Elevation 


li 


5  tb 


-Nails 


Longitudinal  Section 


//          i 

H» — is  y2 — H 

Gate 


FIG.  10. — Delivery  gate  in  use  in  Imperial  Valley,  Cal. 

springs.  The  gate  is  manipulated  by  an  iron  handle  or  wooden 
frame  fastened  to  the  gate.  Fig.  10  shows  the  essential  features 
of  this  design. 

The  chief  points  to  be  considered  in  the  installation  of  such 
structures  are:  (1)  To  secure  an  advantageous  location  in 
tapping  the  canal  so  that  water  can  be  readily  conveyed  from  it 
to  the  highest  point  of  the  farm  to  be  irrigated;  (2)  to  take  the 
necessary  precautions  to  render  the  structure  secure  by  cut-off 
walls  and  earth  puddling  and  packing;  and  (3)  to  place  the  gate 
on  such  a  level  that  it  will  draw  its  full  supply  when  the  canal 
is  only  partly  full. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  43 

CULVERTS. — Various  devices  are  used  to  conduct  the  flow  of 
ditches  across  roads.  A  loose  plank  bridge  or  else  a  culvert 
fon nod  of  four  planks  of  the  requisite  size  and  length  are  both 
quite  common.  So  is  the  loose  plank  bridge.  Unless  lumber  is 
cheap  the  short  life  of  the  former  and  the  inconvenience  of 
the  latter  render  it  worth  while  adopting  a  more  durable  struc- 
ture. Perhaps  the  best  substitute  for  lumber  is  the  metal  pipe 
and  one  of  the  most  durable  and  easily  installed  pipes  is  the 
corrugated  culvert  pipe,  Fig.  11,  made  of  ingot  iron.  This  is 
made  in  sizes  ranging  from  8  to  84  inches  in  diameter  and  two 
or  more  shipping  lengths  may  be  riveted  together  if  necessary. 
In  depressed  crossings  and  wherever  the  pipe  is  under  water 
pressure  the  seams  of  the  pipe  should  be  calked.  The  retail 


I 


FIG.  11. — Corrugated  pipe  of  ingot  iron  used  for  culverts. 

prices  range  from  65  cents  per  foot  for  an  8-inch  pipe  to  $1  and 
over  for  a  15-inch  pipe. 

WATER  FOR  DOMESTIC  USES. — The  settler  under  an  irrigation 
enterprise  has  seldom  an  opportunity  to  obtain  water  from 
either  springs  or  reservoirs  for  culinary  and  stock  purposes. 
As  a  rule  such  supplies  are  obtained  from  the  main  canal  or  one 
of  its  distributaries  or  else  from  wells.  Before  canal  water  can 
be  used  for  domestic  purposes  with  safety  to  health  it  should 
be  filtered.  Filters  are  sometimes  made  by  inserting  a  partition 
wall  of  porous  brick  within  a  cistern  and  allowing  the  canal  water 
to  filter  through  the  wall.  This  practice  is  not  to  be  recom- 
mended on  account  of  the  difficulty  in  cleaning  or  removing  the 


44 


USE  OF  WATER  IN  IRRIGATION 


filter  which  soon  becomes  foul  and  clogged.  A  better  plan  is 
to  filter  the  water  in  a  separate  vessel  and  conduct  it  from  the 
filter  to  the  cistern  where  only  pure  water  is  stored.  The  filter 
may  consist  of  a  concrete  box  with  coarse  gravel  in  the  bottom 
and  a  depth  of  15  inches  of  sand  on  top.  A  large  oak  barrel  is 
a  good  substitute  for  the  concrete  box.  In  using  a  barrel  a  false 
bottom  is  inserted  2  or  3  inches  above  the  true  bottom  and 
pierced  with  a  number  of  holes  which  are  covered  with  a  brass 
wire  screen.  The  filter  consists  of  a  thin  layer  of  gravel,  about 
15  inches  of  sand  and  the  same  depth  of  water.  The  filtered 
water  is  conducted  through  a  small  pipe  from  the  bottom  of  the 


Inlet 


FIG.  12. — Concrete  cistern  for  farm  use. 

barrel  direct  to  the  cistern.  When  the  cistern  is  filled  the  sand 
should  either  be  discarded  or  else  exposed  to  the  sun  and  air  until 
again  used. 

The  concrete  cistern  shown  in  Fig.  121  may  serve  as  a  model 
with  the  exception  of  the  partition  wall  which  is  of  doubtful 
utility.  In  constructing  a  cistern  of  this  kind,  make  a  circular 
excavation  16  inches  wider  than  the  desired  diameter  of  the 
cistern  and  about  16  inches  deeper  than  the  desired  depth. 
Make  a  cylindrical  form  as  shown  in  the  figure,  the  outside  diam- 

1  Bui.  57,  U.  S.  Dept.  of  Agri. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  45 

eter  of  which  will  be  the  inside  diameter  of  the  cistern.  Mix 
the  concrete  in  small  batches  fairly  wet  and  tamp  in  between  the 
form  and  the  earth.  To  construct  the  conical  portion  build  a 
floor  across  the  top  of  the  cylindrical  form,  leaving  a  hole  of  the 
desired  size  in  the  center.  Brace  the  floor  well  with  uprights 
from  the  cistern  bottom.  Build  a  cone-shaped  mould  of  wet  earth 
or  sand  and  lay  the  concrete  and  reinforcing  on  this  cone.  Allow 
it  to  set  and  harden  well  before  removing  the  forms  and  earth. 


FIG.  13. — Small  electrically  driven  pumping  plant. 

A  large  number  of  different  types  of  wells  are  used  throughout 
the  arid  region  to  secure  potable  water.  The  most  suitable  type 
to  select  depends  to  a  great  extent  on  local  conditions  and  the 
practice  followed  in  the  neighborhood  affords  the  best  guide. 
One  can  usually  secure  the  services  of  a  contractor  having  the 
necessary  equipment  who  will  undertake  to  sink  or  bore  a  well 
at  a  certain  price  per  foot. 

Where  it  is  desirable  to  combine  water  supply  for  domestic 
purposes  with  that  of  irrigation  for  a  garden,  lawn,  shade  trees, 


46  USE  OF  WATER  IN  IRRIGATION 

or  small  orchard  the  water  may  be  pumped  from  a  canal,  well, 
or  other  source  by  means  of  a  windmill,  gasoline  engine  or  motor. 

Where  a  small  pumping  plant  is  needed  to  furnish  water 
for  culinary  and  stock  purposes  as  well  as  the  irrigation  of  a 
garden  and  orchard  the  arrangement  shown  in  Fig.  13  may  be 
found  suitable.1 

A  standpipe,  tank,  or  reservoir  is  often  a  necessary  part  of 
small  water  supplies  designed  to  serve  a  number  of  purposes. 
If  the  right  elevation  can  be  obtained  a  reinforced  concrete  stand- 


FIG.  14. — Reservoir  and  pumping  plant. 

pipe  forms  an  excellent  part  of  a  pumping  plant  since  it  can 
be  designed  in  such  a  way  as  not  only  to  store  considerable  water 
but  to  act  as  an  equalizing  and  distributing  reservoir. 

In  a  flat  country  the  pumped  water  is  usually  stored  in  an 
elevated  tank.  Concrete  is  too  heavy  for  such  a  purpose  but 
redwood  stave  pipe  of  large  diameters  may  be  substituted. 

Where  conditions  are  favorable,  a  reservoir  should  be  sub- 
stituted for  the  standpipe  and  tank  on  account  of  its  cheap- 

1  The  Use  of  Small  Water  Supplies  for  Irrigation  by  the  author,  Yearbook 
of  U.  S.  D.  A.,  1907. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  47 


ness,  durability  and  larger  capacity.  The  reservoir  and  pump- 
ing plant  shown  in  Fig.  14  while  somewhat  too  large  and  costly 
for  a  farmer's  use,  may  serve  as  a  sort  of  model  for  a  plant  of 
small  dimensions. 

12.  Pipes  and  Pipe  Systems  for  the  Farm. — The  materials 
composing  the  pipes  most  commonly  used  by  irrigators  are 
concrete,  clay,  wood,  and  metal.  A  brief  description  of  each  of 
these  kinds  follows: 

CONCRETE  PIPE. — This  kind  of  pipe  is  used  quite  generally  in 
southern  California  for  conveying  irrigation  water  underground 
without  pressure  or  under  low  heads  not  exceeding  10  to  15  feet. 
Mr.  C.  E.  Tait,  Irrigation  Engineer  of  the  Department  of  Agri- 
culture, states  that  "a  good  pipe  for  the  smaller  sizes  is  made 
from  a  1  to  3  mixture  consisting  of  5  parts  cement,  6  parts  sand 
and  9  parts  gravel.  A  larger  proportion  of  gravel  may  be  used  in 
the  larger  sizes.  A  good  pipe  may  also  be  made  of  cement,  sand 
and  crushed  rock,  no  particle  being  larger  than  one-half  the 
thickness  of  the  pipe." 

TABLE  No.  12 


Size  of  pipe 

Lineal  feet 
per  barrel 
of  cement 

Lineal  feet 
per  cu.  yd. 
of  gravel 

Cost  data  per  lineal  foot 

Cement 

Gravel 

Mould- 
ing 

Coating 

Total 

4  in. 

126-130 

174 

$0.023  ;$0.006  j$0.020   $0.003 

$0.052 

6  in. 

82-100 

112 

0.036 

0.009 

0.020 

0.003 

0.068 

8  in. 

64-  76 

87 

0.047 

0.011 

0.022 

0.003 

0.083 

10  in. 

48-  56 

64 

0.062 

0.015 

0.025 

0.003 

0.105 

12  in. 

36-  44 

50 

0.083 

0.020 

0.028 

0.004 

0.135 

14  in. 

28-  30 

40 

0.108 

0.025 

0.032 

0.005 

0.170 

16  in. 

26-  28 

34 

0.115 

0.029 

0.038 

0.006 

0.188 

18  in. 

22-  26 

28 

0.136 

0.036 

0.042 

0.007 

0.266 

20  in. 

18-  20 

23 

0.166 

0.043 

0.100 

0.008 

0.317 

24  in. 

12-  14 

18 

0.250 

0.055 

0.110 

0.009 

0.424 

30  in. 

8-  10 

11 

0.375 

0.090 

0.150 

0.011 

0.626 

36  in. 

6-8                8 

0.500 

0.125 

0.200 

0.012 

0.837 

Failures  in  concrete  pipe  have  been  largely  due  to  lean  mix- 
tures, the  use  of  sand  mixed  with  earth  and  improper  moulding. 
A  weak  unreliable  pipe  is  likely  to  result  when  the  voids  in  the 
sand  are  not  filled  with  cement,  when  earthy  material  is  in- 
corporated in  the  mixture  or  when  the  mixture  is  too  dry  when 
moulded.  The  porosity  of  concrete  pipe  is  reduced  and  the  carry- 


48  USE  OF  WATER  IN  IRRIGATION 

ing  capacity  is  increased  by  the  application  to  the  inner  surface 
of  a  cement  brush  coating. 

The  prices  for  materials  in  1914  in  southern  California  were 
for  cement  delivered  $3  per  barrel,  sand  and  gravel  $1  per  cubic 
yard,  tampers  $3  and  mixers  $2.25  per  day  of  9  hours.  The 
quantities  of  materials  used,  their  respective  costs  and  the  cost 
of  the  various  processes  in  making  pipe,  exclusive  of  overhead 
charges  and  profits  are  given  in  Table  12. 

MOULDING  THE  PIPE. — Concrete  pipe  as  made  in  southern  Cali- 
fornia for  the  farmer's  use  is  moulded  in  2-foot  lengths  with 
beveled  lap  joints.  Since  the  price  of  moulds  for  pipe  between  6 
and  12  inches  in  diameter  varies  from  $50  to  $100  per  set  the 
tendency  is  to  use  the  smallest  possible  number.  This  effort 
to  economize  frequently  results  in  a  brittle  pipe  caused  by  the 
use  of  too  dry  a  mixture,  such  a  mixture  requiring  less  time  in 
the  moulds.  To  obviate  this  difficulty  and  increase  the  output 
from  each  set  of  moulds  thin  metal  cylinders  are  sometimes 
introduced  in  the  moulds  and  allowed  to  remain  for  some  time 
around  the  freshly  moulded  pipe  after  its  removal  from  the  moulds. 
In  this  way  a  wetter  mixture  resulting  in  a  stronger  pipe  can  be 
made. 

The  making  of  concrete  pipe  is  still  in  a  formative  stage. 
In  recent  years  various  methods  have  been  designed  and  pat- 
ented. Some  of  these  will  doubtless  prove  useless  or  impracti- 
cable but  by  combining  the  best  features  of  several  designs 
methods  will  become  standardized  in  time. 

Successful  attempts  have  been  made  to  lessen  the  arduous 
and  slow  process  of  hand  tamping  by  placing  the  mould  on  a 
revolving  table  and  operating  the  tamping-bar  by  machinery. 
The  same  end  is  perhaps  better  attained  by  subjecting  the  table 
to  a  succession  of  sudden  and  brief  motions  first  in  a  horizontal 
and  then  in  a  vertical  direction.  These  alternating  jars  serve 
to  pack  the  material  in  a  dense,  uniform  mass.  This  method 
is  known  as  the  Jagger  system  and  seems  to  be  especially  well 
adapted  to  reinforced  pipe. 

Another  method  is  to  subject  the  freshly  moulded  pipe  to 
the  action  of  superheated  steam  which  greatly  hastens  the 
setting  of  the  concrete  and  permits  the  pipe  to  be  withdrawn 
from  the  moulds  without  any  serious  delay. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  49 

In  the  manufacture  of  reinforced  concrete  pipe  in  Australia 
to  convey  water  for  domestic,  power,  and  irrigation  purposes  and 
for  electric  conduits,  the  packing  is  done  by  means  of  centrifugal 
force.  The  mould,  which  is  6  feet  or  more  in  length,  is  placed  on 
journals  in  a  horizontal  position.  Light  reinforcing  in  the  form 
of  a  cylinder  is  then  inserted  in  the  mould  after  which  a  wet 
concrete  mixture  is  gradually  poured  in  from  each  end.  As  the 
concrete  enters  the  mould  the  latter  revolves,  at  first  slowly  and 
later  at  a  high  rate  of  speed.  The  centrifugal  force  thus  de- 
veloped not  only  packs  the  concrete  but  forms  a  smooth  finish 
on  the  inner  surface  of  the  pipe.  The  sections  are  true  cylinders 
and  reinforced  collars  are  placed  around  abutting  joints.  This 
pipe  is  used  under  pressures  of  75  pounds  or  more  per  square 
inch. 

VITRIFIED  CLAY  PIPE. — Pipe  made  of  moulded  clay,  kiln-burned 
and  glazed  is  extensively  used  to  conduct  sewage  in  the  sewer 
systems  of  towns  and  cities.  The  requirements  for  this  service 


FIG.  15. — Fittings  for  vitrified  clay  pipe. 

are  quite  rigid  and  the  pipe  which  is  rejected  by  the  sewer  in- 
spector can  frequently  be  purchased  at  a  low  figure.  In  this  way 
the  irrigator  who  resides  within  hauling  distance  of  a  town  or 
city  can  usually  obtain  from  the  municipality  or  the  clay  pipe 
company  a  serviceable  water  pipe  for  low  heads  at  reasonable 
prices. 

In  southern  California  the  rejected  sewer  pipe  is  classified  into 
three  grades  known  as  Nos.  1,  2,  and  3  water  pipe.  The  defects 
in  No.  1  grade  are  not  serious  and  can  be  depended  on  to  stand 
a  head  of  20  to  30  feet  in  the  smaller  sizes  and  15  to  20  feet  in 
the  larger  sizes.  The  No.  2  grade  consists  of  pipe  which  is 
cracked  in  the  main  part  of  the  joint  or  length  and  withstands 
less  pressure  than  No.  1.  No.  3  grade  is  used  only  for  drainage, 
being  usually  cheaper  than  the  tile.  The  prices  of  grades  1  and 

4 


50 


USE  OF  WATER  IN  IRRIGATION 


2  in  3-foot  lengths,  f.o.b.  cars  Los  Angeles,  are  at  this  writing 
(1914)  as  follows: 


TABLE  No.  13 


Size 

No.  1   Grade.      Cents  per  ft.  |  No.  2  Grade.      Cents  per    ft. 

3  in. 

4  7/8 

4  1/8 

4  in. 

6  1/2 

5  1/2 

5  in. 

8  1/8 

6  7/8 

6  in. 

9  3/4 

8  1/4 

8  in. 

12  3/8 

10  1/8 

10  in. 

16  1/2 

13  1/2 

12  in. 

20  5/8 

16  7/8 

14  in. 

27  1/2 

22  1/2 

16  in. 

34  3/8 

28  1/8 

18  in. 

41  1/4 

33  3/4 

20  in. 

56  7/8 

48  1/8 

22  in. 

71  1/2 

60  1/2 

24  in. 

81   1/4 

68  3/4 

Manufacturers  of  clay  pipe  furnish  standpipes  and  other 
fittings  similar  to  those  furnished  by  the  concrete  pipe  makers. 
The  stand  shown  in  Fig.  15a  is  used  for  orchard  irrigation.  A 
special  fitting  shown  in  Fig.  15b  is  also  made  for  the  insertion  of 
a  gate  on  a  pipe  line  and  a  T  joint  with  an  " alfalfa"  valve  in 
position  on  the  vertical  branch  as  shown  in  Fig.  15c. 

WOOD  PIPE. — The  various  kinds  of  wood  pipe  used  to  convey 
water  for  irrigation  purposes  belong  to  one  of  two  general  types. 
One  of  these  is  the  continuous  stave  pipe  and  the  other  the 
machine  banded  pipe.  Since  the  former  is  only  built  in  medium 
and  large  sizes  in  which  the  diameters  run  from  1  to  12  feet  it  is 
not  well  adapted  to  the  farmer's  needs  and  for  that  reason  will 
not  be  considered  here. 

The  factory  for  making  machine-banded  pipe  in  San  Francisco, 
California,  uses  redwood;  those  located  in  Portland,  Oregon, 
Tacoma  and  Seattle,  Washington,  and  Vancouver,  B.  C.,  use  fir. 
In  the  States  of  'New  York  and  Pennsylvania  the  pipes  are  made 
of  white  pine  and  tamarack  while  in  Louisiana  cypress  is  con- 
sidered the  most  suitable  wood. 

A  quarter  of  a  century  and  less  ago,  machine-banded  pipe  con- 
sisted wholly  of  logs  turned  in  a  lathe,  machine-bored  and 
wrapped  with  flat  steel  bands.  Staves  8  to  12  feet  in  length  in 
the  eastern  factories  and  up  to  20  feet  in  length  in  the  western 


NECESSARY    EQUIPMENT    AND    STRUCTURES  51 

factories  have  since  been  substituted  for  bored  logs.  The 
staves  which  vary  in  thickness  from  1  to  1  3/4  inches  are  held  to- 
uvthc.r  by  galvanized  steel  wire  spaced  far  apart  or  close  accord- 
ing as  the  internal  pressure  of  the  water  is  low  or  high.  In  some 
factories  flat  bands  of  steel  14  to  16  gauge  are  used  instead  of  the 
round  wire.  After  the  pipe  is  banded  and  the  ends  are  milled 
for  couplings  each  section  is  dipped  in  a  bath  of  hot  asphalt  and 
when  withdrawn  is  rolled  in  sawdust  or  shavings. 

The  joints  are  made  in  various  ways.     A  common  form  for 
low  pressures  is  that  of  the  mortise  and  tenon  joint.    The  joint 


FIG.  16. — Forms  of  joints  for  wood  pipe. 

is  reinforced  when  the  pressure  requires  it.  Sometimes  tenons 
are  made  on  both  ends  of  each  section  and  the  coupling  is  made 
by  means  of  collars.  All  three  forms  are  shown  in  Fig.  16.  In 
common  with  other  kinds  of  pipes  the  joints  in  wood  pipe  are 
the  chief  source  of  trouble  and  expense. 

According  to  S.  O.  Jayne,  Irrigation  Engineer,  U.  S.  Depart- 
ment of  Agriculture,  the  cost  of  laying  wood  pipe  exclusive  of 
earthwork,  backfilling  and  haulage  varies  from  2  cents  per  lineal 
foot  for  pipes  4  to  6  inches  in  diameter  up  to  6  cents  for  pipes  24 
inches  in  diameter. 


52 


USE  OF  WATER  IN  IRRIGATION 


The  prices  and  weights  per  lineal  foot  of  machine-banded  pipe 
f.o.b.  cars,  Seattle,  Washington,  follows: 

TABLE  No.  14 


Diam- 
eter 

Head, 
feet 

Price 

Weight, 
pounds 

Diame- 
ter 

Head 

Price 

Weight, 
pounds 

2  in. 

50 

0.087 

3.1 

10  in. 

50 

0.268 

13.1 

100 

0.09 

3.2 

100 

0.347 

14.7 

150 

0.092 

3.2 

150 

0.392 

15.7 

200 

0.10 

3.4 

200      ;  0.455 

17.3 

250 

0.105 

3.5 

250 

0.479 

18.4 

300 

0.116 

3.6 

300 

0.503 

19.4 

4  in. 

50 

0.129 

5.8 

12  in. 

50 

0.322 

16.8 

100 

0.131 

5.9 

100 

0.413 

18.9 

150 

0.134 

6.0 

150 

0.450 

19.8 

200 

0.166 

6.3 

200 

0.532 

21.7 

250 

0.176 

7.0 

250 

0.618 

23.8 

300 

0.189 

7.3 

300 

0.660 

25.3 

6  in. 

50 

0.163 

8.3 

14  in. 

50 

0.445 

21.3 

100 

0.168 

8.9 

100 

0.550 

23.0 

150 

0.184 

9.1 

150 

0.629 

25.3 

200 

0.226 

9.6 

200 

0.745 

28.2 

250 

0.242 

10.0 

250 

0.834 

29.9 

300 

0.258 

10.4 

300 

0.916 

32.3 

8  in. 

50 

0.203 

10.3 

16  in. 

50 

0.547 

24.7 

100 

0.224 

10.5 

100 

0.639 

26.9 

150 

0.292 

12.8 

150 

0.734 

29.3 

200 

0.332 

13.7 

200 

0.871 

33.4 

250 

0.366 

15.6 

250 

0.987 

36.2 

300 

0.387 

16.2 

300 

1.132 

40.2 

METAL  PIPES. — Space  will  not  permit  even  a  brief  description 
of  each  kind  of  metal  pipe  used  by  irrigators.  References 
are  made  to  the  galvanized  iron  pipe  in  Art.  19  and  to  the  cor- 
rugated pipe -in  Art.  11.  Notwithstanding  the  large  variety  in 
the  market  by  far  the  most  common  is  the  steel-riveted  pipe. 
This  pipe  may  be  purchased  in  a  large  number  of  sizes  ranging 
from  4  to  30  inches  and  over  in  diameter  and  capable  of  with- 
standing heads  of  50  to  300  feet.  Each  joint  of  pipe  is  made  of 
a  single  sheet  of  steel  which  is  sized,  punched,  rolled  and  riveted. 
A  number  of  these  joints  are  then  riveted  together  making  a 


NECESSARY    EQUIPMENT    AND    STRUCTURES  53 

shipping  length  of  about  30  feet.  Each  length  is  immersed  in  a 
}>:ith  of  hot  asphalt  before  being  stacked  up  in  the  shipping 
yards.  For  all  sizes  up  to  12  inches  designed  for  ordinary  pres- 
sures the  lengths  are  simply  driven  together,  the  smaller  joint 
of  one  end  telescoping  the  larger  joint  of  the  adjacent  length. 
For  high  pressures  and  large  sizes  the  circular  seams  are  single 
riveted  and  the  seams  may  be  split-calked.  For  low  heads, 
lighter  and  less  expensive  pipe  of  galvanized  iron  from  20  to 
24  gauge,  both  coated  and  uncoated,  has  during  the  past  few 
years  come  into  somewhat  extensive  use  throughout  certain 
sections  of  the  Northwest. 

The  following  table  gives  the  list  prices  of  steel-riveted  pipe 
in  Los  Angeles,  California,  in  1914,  these  prices  being  subject  to 
a  discount  of  about  15  per  cent. 

TABLE  No.  15 
Size  16-Gauge  14-Gauge  12-Gauge 

4  in.  $0.19  $0.22  

5  in.  0.23  0.27  

6  in.  0.28  0.32  $0.41 
Tin.  0.31  0.37                        0.48 
Sin.  0.34  0.40                        0.52 
9  in.  0.38  0.42                         0.57 

10  in.  0.41  0.47  0.62 

11  in.  0.43  0.49  0.65 

12  in.  0.46  0.55  0.69 

PIPE  SYSTEMS. — As  irrigation  practice  develops  the  unlined 
ditch  will  gradually  give  place  to  pipes.  Of  late  years  more  or 
less  substitution  of  this  kind  has  been  made  in  western  localities 
where  water  is  scarce  and  costly  and  where  large  crop  returns  are 
secured.  The  same  is  true  in  the  eastern  part  of  the  United 
States  where  water  supplies  are  abundant  and  cheap.  The 
eastern  irrigator  adopts  the  open  ditch  only  as  a  last  resort. 
He  considers  pipes  the  more  efficient  and  economical  for  the 
following  reasons.  They  are  laid  underground  beneath  the 
deepest  furrow,  there  is  practically  no  loss  in  conveyance,  and 
time  and  labor  are  saved  in  applying  the  water.  In  the  case  of 
open  ditches  the  western  irrigator  has  to  weigh  their  cheapness 
against  a  number  of  disadvantages.  Among  these  may  be  men- 
tioned the  returns  which  might  be  derived  from  the  valuable 


54 


USE  OF  WATER  IN  IRRIGATION 


ground  occupied  by  open  ditches,  the  damage  done  by  noxious 
weeds  which  grow  on  their  banks,  the  loss  of  water  by  absorp- 
tion, the  structures  required  to  span  them,  the  heavy  mainte- 
nance charge,  the  inconvenience  of  crossing  and  recrossing  them 
with  teams  and  implements  and  the  difficulty  of  distributing 
water  from  such  channels. 

The  arrangement  of  pipe  systems  for  irrigation  is  not  unlike 
that  for  domestic  water  supplies  in  cities  since  the  requirements 


/Irrigating  Flume 


Irrigating  Flume      Lincoln  Avenue 


Hydrant 


FIG.  17. — Orchard  tract  showing  streets  and  pipe  laterals. 

are  similar.  There  is  usually  the  main  conduit  from  which  the 
feed  pipes  extend.  The  water  carried  by  each  feed  pipe  is  dis- 
tributed through  lateral  pipes  which  supply  the  various  farms  or 
fields.  In  cities  water  for  domestic  purposes  is  frequently 
metered  out  to  each  consumer.  The  same  course  has  been  fol- 
lowed by  irrigation  companies.  A  better  and  cheaper  plan  is 
to  measure  the  water  diverted  into  each  distributing  pipe  and 
determine  all  water  deliveries  by  the  quantity  carried  in  each 
and  the  number  of  hours  it  is  used. 

On  the  Gage  Canal  system  in  Riverside  County,  California, 


NECESSARY    EQUIPMENT    AND    STRUCTURES  55 


the  water  supply  for  the  tiers  of  40-acre  tracts  is  taken 

the    canal    in    riveted    steel 

pipes  varying  from  6  to  10 

inches    in    diameter.     These 

larger  mains   are  connected 

with  4-,  5-,  and  6-inch  lateral 

pipes  of  the  same  material, 

which   convey  the  water  to 

the    highest    point    of   each 

10-acre  Jract.     This  general 

arrangement  is  shown  in  the 

sketch,  Fig.  17. 

Fig.  18  shows  the  plan  of 
the  pipe  system  of  the  irri- 
gated farm  of  Granville  W. 
Leeds  at  Rancocas,  New 
Jersey,  as  designed  and  in- 
stalled by  Milo  B.  Williams, 
Irrigation  Engineer  of  the 
Department  of  Agriculture. 
In  this  system  a  24-horse- 
power  gasoline  engine 
(Gray),  driving  a  No.  3 
American  2-stage  horizontal 
centrifugal  pump  raises  water 
out  of  Rancocas  Creek  to  a 
maximum  height  of  88  feet.  Barn 
A  5-inch  galvanized  steel 
pressure  main  conveys  the 
water  from  the  pump  to  a 
standpipe.  From  there  the 
water  is  distributed  through  Hot= 
small  overhead  pipes  to  about 
9  acres  which  are  irrigated  by 
the  overhead  spray  method. 
Under  a  pressure  of  30  pounds 
per  square  inch  at  the  nozzles 
of  the  spray  pipes  the  plant 
discharges  from  265  to  300  gallons  per  minute. 


from 


56 


USE  OF  WATER  IN  IRRIGATION 


Underground  Main 

FIG.  19. — Underground  pipe,  hydrant,  and  distributor  on  an  eastern  truck 

farm. 


FIG.  20. — Details  of  hydrant  shown  in  Fig.  19. 


FIG.  21. — Detail  of  valve  on  distributor  shown  in  Fig.  19. 


NECESSARY    EQUIPMENT    AND    STRUCTURES  57 

Leading  out  from  the  centrally  located  standpipe  is  another 
f  low  pressure  pipe  of  8-inch  vitrified  clay  which  is  reduced 
farther  on  to  6-inch  pipe.  These  pipes  are  laid  beneath  the 
surface  so  as  not  to  interfere  with  plows  or  subsoilers  and  fit  into 
the  topography  of  the  tract,  Fig.  19.  Hydrants  or  stands  of 
the  type  shown  in  Fig.  20  are  placed  at  the  head  of  every  other 
tree  row  or  approximately  44  feet  apart.  A  portable  distribut- 
ing pipe  with  openings  spaced  about  5  feet  apart  and  controlled 
by  special  valves,  Fig.  21,  is  attached  by  canvas  hose  to  each 
hydrant  in  turn  for  the  irrigation  of  each  strip  between  the  hy- 
drants. The  capacity  of  the  plant  when  water  is  conveyed  from 
the  standpipe  through  vitrified  pipe  and  distributed  over  the 
surface  in  furrow  irrigation  varies  from  300  to  350  gallons  per 
minute.  The  cost  of  this  plant  complete  was  $3440  or  $123 
per  acre  but  the  extra  returns  from  the  irrigated  area  in  the  way 
of  larger  and  better  crops  has  rendered  it  a  highly  profitable 
investment. 

13.  Pumping  Plants.  Source  of  Supply. — Only  a  relatively 
small  part  of  pumped  water  is  derived  from  surface  supplies 
such  as  streams,  lakes,  reservoirs  and  canals.  The  utilization 
of  these  is  comparatively  easy  since  all  that  is  required  is  a 
direct  connection  between  the  pump  and  the  water  by  means  of 
a  suction  pipe. 

By  far  the  greater  part  of  the  water  raised  by  pumping  plants 
is  found  at  varying  depths  beneath  the  surface.  The  water  so 
found  does  not  move  as  in  streams  freely  from  place  to  place  in 
more  or  less  large  volumes.  It  is  divided  up  into  an  innumerable 
number  of  small  particles  which  are  enclosed  for  the  time  being 
within  the  interstices  of  earth  and  rock.  Some  of  these  materials 
are  either  so  fine  in  texture  or  else  so  dense  that  they  virtually 
imprison  the  water  within  their  mass.  Other  substances  are 
more  open  in  texture  and  these  permit  the  slow  passage  of  water 
through  their  open  spaces.  Such  formations  are  termed  water- 
bearing strata  which  receive  and  give  off  water  to  the  extent  of 
20  to  30  per  cent,  of  their  volume. 

The  percentage  of  open  space  in  some  material  may  exceed 
40  per  cent.  When,  however,  the  voids  of  coarse  material  such 
:is  gravel  are  filled  with  sand  and  those  of  the  sand  with  silt  or 
clay,  the  water-holding  capacity  of  the  material  is  greatly  dimin- 


58  USE  OF  WATER  IN  IRRIGATION 

ished  and  the  amount  of  water  which  will  pass  through  it  in  a 
given  time  is  still  further  diminished.  Whether  the  material 
composing  a  water-bearing  stratum  is  of  one  kind  or  of  several 
the  amount  of  water  which  flows  from  it  into  a  well,  for  example, 
is  always  less  than  the  amount  required  for  saturation.  A 
certain  percentage  clings  to  each  particle  of  silt,  sand  or  gravel 
and  can  not  be  dislodged  by  the  force  exerted  by  gravity.  As  a 
result  of  tests  conducted  by  V.  M.  Cone  and  the  writer  in  1907 
the  fine  sandy  loam  of  Fresno  County,  California,  contained  30.5 
per  cent,  of  open  space  and  gave  off  22  per  cent,  after  being 
saturated.  A  clay-sand  loam  of  the  same  locality  contained  40 
per  cent,  of  open  space  and  gave  off  25  per  cent.  In  the  coarser 
material  penetrated  by  many  wells  the  open  space  or  porosity 
may  be  greater  and  such  material  may  give  off  from  a  saturated 
mass  fully  30  per  cent,  by  volume  of  water.  Under  some  con- 
ditions this  underground  water  moves  in  a  generally  horizontal 
direction  down  a  given  slope  at  a  slow  rate  of  speed — often  not 
more  than  a  few  feet  per  day.  This  is  true  of  beds  of  streams 
which  flow  over  porous  material.  When  only  a  small  part  of  this 
so-called  underflow  *is  withdrawn  by  pumps,  the  deficiency  is 
speedily  restored  by  the  inflow.  When,  however,  more  water  is 
withdrawn  than  the  inflow  can  replenish  the  supply  diminishes 
unless  a  low  level  is  tapped. 

Under  other  conditions  there  is  little  more  than  an  up  and 
down  movement  of  the  underground  water  caused  by  precipi- 
tation and  floods  on  the  one  hand  and  deep  percolation  on 
the  other.  In  such  cases  the  withdrawal  of  water  during  an  ir- 
rigation season  usually  lowers  the  water  table  but  if  this  is 
restored  when  the  pump  ceases  to  run  or  at  the  close  of  the 
season  or  year  no  apprehension  need  be  felt.  It  is  only  when 
the  water  table  is  permanently  lowered  as  a  result  of  pumping 
from  season  to  season  that  a  scanty  or  unreliable  supply  is 
indicated. 

In  calling  attention  to  the  longitudinal  and  vertical  move- 
ments of  underground  water  it  is  well  to  bear  in  mind  that  the 
water  contained  in  any  given  water-bearing  strata  may  be  sub- 
jected to  both  movements  in  the  same  period  of  time. 

According  to  the  census  there  were  in  1910,  15,803  pump- 
ing plants  of  all  kinds  in  the  United  States.  Out  of  this  total 


NECESSARY    EQUIPMENT    AND    STRUCTURES  59 


9297  were  found  in  California  and  1897  in  the  rice  belt  of  the 
Gulf  States.  Since  78  per  cent,  of  this  kind  of  irrigation  is 
confined  to  these  two  localities  the  information  herein  given 
concerning  this  subject  will  likewise  be  confined  to  these  same 
localities. 

WELLS. — According  to  C.  E.  Tait,  the  most  common  sizes  of 
drilled  wells  for  new  plants  in  southern  California  at  this  writing 
(1914)  are  12,  14,  16,  and  20  inches  in  diameter.  A  few  24- and 
26-inch  wells  are  also  in  use.  The  increase  in  size  in  recent 
years  has  been  largely  due  to  two  causes.  The  larger  circum- 
ference of  the  casing  permits  more  openings  to  be  made  and 
more  water  to  enter  from  the  adjacent  gravel.  They  are  also 
better  suited  to  the  use  of  deep  well  pumps  of  the  plunger  and 
turbine  types  in  that  they  permit  a  long  stroke  at  low  speed. 


FIG.  22. — Well  casing. 

The  casing  consists  of  a  double  thickness  of  riveted  steel 
sheets  2  feet  long  arranged  as  in  Fig.  221  and  broken  jointed. 
The  cost  of  casing  per  foot  for  various  diameters  and  thickness 
of  metal  subject  to  a  discount  of  30  per  cent,  is  as  follows: 

TABLE  No.  16 


Diameter,  inches 


16-Gauge  14-Gauge 


12-Gauge 


10-Gauge 


7 

$0  59 

$0  68 

10 

0  83 

0  99 

$1  20 

12 
14 
16 
20 

0.90 
1.08 
1.21 

1.06 
1.20 
1.33 
1  57 

1.37 
1.62 
1.94 
2.23 

$1.78 
1.97 
2.17 
2.64 

24 

2.69 

3.20 

1  Bui.  236,  O.  E.  S.,  U.  S.  D.  A. 


60  USE  OF  WATER  IN  IRRIGATION 

What  is  known  as  a  starter  is  a  tube  about  20  feet  long  riveted 
to  the  bottom  of  the  casing.  This  consists  of  a  triple  thickness 
of  metal  for  large  wells  and  for  wells  in  bowlders  or  rock.  A 
steel  shoe  or  ring  is  in  turn  riveted  to  the  bottom  of  the  starter. 
A  3-ply,  12-gauge  starter  for  a  12-inch  well  costs  $1.80  per  foot, 
while  a  12  X  3/4  inch  ring  costs  $16. 

Wells  in  southern  California  are  drilled  by  contract.  The 
equipment  consists  of  a  California  portable  rig  costing  $500  to 
$600  without  the  tools.  In  starting  a  well  a  hole  is  first  bored 
and  the  starter  inserted.  A  sand  bucket  is  then  used  to  make 
the  excavation  unless  rock  is  encountered.  The  rig  is  provided 
with  hydraulic  jacks  which  apply  a  pressure  of  100  tons  or  less 
to  an  iron  ring  which  rests  on  the  top  of  the  casing.  The  cost 
of  drilling  in  sand  or  clay  exclusive  of  casing  is  $1.50  per  foojt 
for  a  12-inch  well.  Contractors  are  usually  protected  by  a 
provision  inserted  in  the  contract  to  the  effect  that  if  bowlders 
or  rock  are  encountered  requiring  more  than  2  hours  to  bore 
through  an  extra  charge  will  be  made. 

Strainers,  which  form  so  essential  a  feature  of  many  wells  in 
the  rice  belt,  are  not  necessary  in  southern  California  as  there 
is  no  quicksand  or  very  fine  sand  unmixed  with  coarser  material. 
Water  is  admitted  through  long  vertical  slots  in  the  casing  which 
are  cut  by  a  special  tool  after  the  casing  is  in  place.  The  cross 
sections  of  the  openings  thus  made  are  trapezoidal  in  form,  the 
narrowest  side  being  at  the  outside  to  prevent  clogging.  Four 
vertical  slots  about  20  inches  long  are  made  in  the  circumference 
of  each  joint  of  a  12-inch  casing  opposite  and  slightly  below 
each  water-bearing  stratum. 

In  the  rice  belt,  according  to  C.  G.  Haskell,  Irrigation  Engineer, 
Department  of  Agriculture,  the  hydraulic  rotary  method  for 
drilling  wells  is  the  most  common.  The  equipment  usually 
consists  of  a  derrick  16  feet  square  at  the  bottom  tapering  to  4 
feet  square  at  the  top  and  about  40  feet  high.  The  first  operation 
after  the  derrick  has  been  built  over  the  site  is  to  sink  a  test 
hole  by  using  a  4-inch  pipe  in  order  to  get  a  log  of  the  well.  A 
fish-tail  bit  is  screwed  into  the  lower  end  of  the  pipe  and  its 
cutting  blade  makes  an  opening  somewhat  larger  than  the  pipe 
as  both  are  revolved.  Muddy  water  is  then  pumped  into  the 
pipe  and  is  discharged  under  high  velocities  through  two  1- 


NECESSARY    EQUIPMENT    AND    STRUCTURES  61 

inch  openings  in  the  bit  at  the  lower  end.  The  water  carrying  the 
borings  then  rises  on  the  outside  of  the  pipe  to  the  surface. 
After  the  test  hole  has  been  drilled  to  the  required  depth  the 
pipe  is  removed  from  the  well. 

The  character  of  the  materials,  particularly  those  of  the 
water-bearing  strata  are  known  from  the  log  and  suitable 
strainers  and  other  equipment  can  then  be  ordered  and  trans- 
ported to  the  site.  The  permanent  well  is  then  dug  in  very  much 
the  same  manner  as  the  test  well. 

PUMPS. — For  low  lifts  not  exceeding  30  feet,  the  horizontal 
centrifugal  pump  is  perhaps  the  best  type.  Where  there  is  lit- 
tle fluctuation  in  the  water  table  and  the  lift  is  not  over  25  feet 
they  can  be  installed  on  the  surface  and  belted  or  coupled  direct 
to  engines  and  motors.  The  same  kind  of  pump  can  be  lowered 
in  a  pit  10  to  15  feet  below  the  surface  in  order  to  secure  a  safer 
suction  and  to  adapt  it  to  a  somewhat  higher  lift. 

For  lifts  between  20  and  75  feet  the  single-stage,  vertical  cen- 
trifugal pump  is  commonly  installed.  This  kind  of  pump  may 
be  placed  in  the  bottom  of  an  open  pit  or  shaft  within  safe  suc- 
tion reach  of  the  water  and  if  the  water  lift  is  stable  it  may  be 
directly  connected  to  an  electric  motor  by  vertical  shafting. 

Such  installations  are,  however,  rare  in  southern  California 
on  account  of  the  seasonal  and  periodical  fluctuation  in  the 
water  table. 

For  lifts  ranging  between  75  and  150  feet  the  two-stage,  verti- 
cal centrifugal  pump  is  the  most  common.  The  limit  of  150  feet 
or  less  is  due  largely  to  the  cost  of  the  shaft.  These  shafts  or 
pits  are  6  X  8  feet  or  5  X  7  feet  when  curbed  with  redwood  and 
circular  when  curbed  with  concrete.  The  cost  of  the  excavation 
increases  with  the  depth. 

Owing  to  the  expense  of  digging  a  pit  and  lining  it  with  con- 
crete, which  though  more  expensive  than  redwood  is  in  the  end 
more  economical,  the  tendency  in  late  years  has  been  to  install 
turbine  or  turbine  centrifugal  pumps  for  all  lifts  over  100  feet  and 
thus  dispense  with  the  open  pit. 

The  Layne  and  Bowler  Company  manufactures  a  special  form 
of  centrifugal  pump  which  operates  within  a  steel  casing.  This 
steel  casing  is  inserted  by  the  rotary  process  previously  described 
and  may  be  lowered  50  feet  or  more  below  the  water  level.  In 


62  USE  OF  WATER  IN  IRRIGATION 

this  way  the  pump  is  submerged.  This  type  of  pump  is  well 
adapted  to  conditions  which  prevail  in  the  rice  belt  but  is  little 
used  in  southern  California.  There  the  orchardists  prefer  the 
double-acting,  deep-well  pumps  with  plungers  operating  within 
a  cylinder  of  brass  tubing  and  with  a  specially  designed  power 
head  for  converting  the  rotary  motion  of  the  belt  pulley  into  the 
reciprocating  motion  of  rods  and  plungers  with  quick  return  and 
lap  stroke  to  prevent  pulsations  in  the  discharge  of  water.  This 
type  is  used  for  lifts  of  from  150  to  400  feet. 

For  lifts  between  300  and  400  feet  the  Pomona  Manufac- 
turing Co.,  Pomona,  Cal.,  and  the  Deane  Pump  Works  of  Holyoke, 
Mass.,  make  somewhat  similar  pumps  to  that  just  described  but 
with  three  plungers.  The  lowest  plunger  is  operated  by  a  solid 
rod  placed  within  a  hollow  rod  which  operates  the  middle  plunger 
and  this  in  turn  is  placed  within  a  second  hollow  rod  which 
operates  the  highest  plunger.  With  three  plungers  the  discharge 
of  water  is  fairly  constant  and  in  consequence  the  power  head  for 
this  so-called  triplex  deep- well  pump  does  not  require  the  quick 
return  and  lap  in  stroke  which  form  so  prominent  a  feature  of 
the  double-acting  type. 

ENGINES  AND  MOTORS. — The  power  required  to  raise  water  for 
irrigation  is  now  confined  for  the  most  part  to  gas-burning  engines 
and  electric  motors.  In  localities  far  removed  from  oil  wells, 
gasoline  and,  to  some  extent,  distillate  are  the  staple  fuel  prod- 
ucts for  such  engines.  A  cheaper  power  can  be  produced  by  a 
new  product  of  the  oil  wells  known  as  "tops."  In  heating 
crude  oil  in  tanks  as  a  partial  refining  process  for  use  in  locomo- 
tives the  top  layer  is  removed  and  is  now  marketed  as  a  special 
by-product.  Its  specific  gravity  ranges  from  38  to  40  degrees 
Baume,  its  flashing  point  is  under  100  degrees  and  it  costs  2  3/4 
cents  per  gallon,  f.o.b.  Los  Angeles.  It  is  claimed  that  "tops" 
produces  more  power  per  gallon  than  distillate  which  sells  for 
8  and  9  cents  a  gallon. 

For  small  and  medium-sized  plants  up  to  75  horsepower  the 
most  popular  and  cheapest  at  the  present  time  in  southern  Cali- 
fornia is  a  gasoline  engine  so  modified  as  to  burn  tops  in  its 
cylinder.  A  plant  of  this  kind  was  recently  installed  by  Raught 
Brothers,  Redlands,  California.  It  consists  of  a  cased  well 
16  inches  in  diameter,  a  double-acting  deep- well  pump  and  a 


NECESSARY    EQUIPMENT    AND    STRUCTURES  63 

60-horsepower  gasoline  engine.  The  plant  discharges  75  to  80 
miner's  inches  (673  to  718  gallons  per  minute)  under  a  lift  of 
180  feet  at  a  total  cost,  including  fuel,  attendance,  interest  and 
depreciation,  of  0.0284  cent  per  foot  acre-foot.1 

Owing  to  the  large  output,  the  low  first  cost  and  keen  competi- 
tion, the  price  of  electric  current  has  been  lowered  in  recent 
years.  Electric  current  is  now  supplied  to  pumping  plants 
between  San  Bernardino  and  Los  Angeles  at  the  rate  of  1  cent  per 
K.  W.  hour.  As  compared  with  oil-burning  engines,  induction 
motors  have  a  somewhat  higher  efficiency  and  a  lower  cost  for 
maintenance  and  operation.  They  are,  moreover,  adapted  to 
a  wider  range  of  conditions  and  can  be  more  readily  operated. 

When  a  10-horsepower  gasoline  engine  operates  a  centrifugal 
pump  and  raises  a  volume  of  water  in  a  given  time  equivalent 
to  the  application  of  5  horsepower,  the  efficiency  of  the  plant 
is  said  to  be  as  1  is  to  2,  or  50  per  cent.  The  efficiencies  of  pump- 
ing plants  depend  on  a  wide  range  of  conditions  and  in  con- 
sequence vary  between  wide  limits.  The  experiments  made  by 
Le  Conte  and  Tait  in  California  nearly  a  decade  ago  revealed  the 
fact  that  the  efficiencies  of  many  of  the  plants  tested  varied  from 
30  to  50  per  cent,  and  that  some  of  the  poorest  plants  did  not 
exceed  20  per  cent.  Improvements  since  made  covering  engines, 
pumps  and  installations  have  tended  to  increase  efficiencies  so 
that  the  range  of  the  present  time  lies  between  30  and  75  per  cent. 
Other  conditions  being  similar,  the  small  plant  operating  under 
low  lifts  wastes  the  most  power  and  farmers  who  install  such 
should  not  figure  on  getting  much  more  than  35  per  cent,  of 
useful  work  done. 

1  The  expression  per  foot  acre-foot  means  the  raising  of  1  acre-foot  of 
water  which  is  equal  to  43,560  cubic  feet,  or  325,850  gallons,  through  a 
vertical  elevation  of  1  foot. 


CHAPTER  IV 
METHODS  OF  PREPARING  LAND  AND  APPLYING  WATER 

14.  The  Removal  of  Native  Vegetation. — In  arid  America  few 
places  are  so  barren  as  not  to  produce  plants  of  some  kind,  and 
the  first  step  in  preparing  land  for  irrigation  is  the  removal  of 
this  native  vegetation.  When  this  consists  of  native  grasses,  low 
cacti,  or  rabbit  brush  it  can  be  plowed  under  or  removed  without 
much  extra  expense  but  when  it  consists  of  large  sagebrush, 
greasewood,  mesquite  or  other  plants  of  shrubby  growth  the  cost 
may  be  considerable.  Still  costlier  is  the  removal  of  junipers, 
pines,  or  other  trees — sometimes  of  considerable  size — which  grow 
in  some  of  the  less  arid  sections  where  irrigation  is  practised. 

SAGEBRUSH. — Of  all  the  desert  plants,  sagebrush  is  the  most 
widely  distributed.  It  covers  thousands  of  square  miles  of  the 
Rocky  Mountain  and  Pacific  Coast  states  and  various  methods 
have  been  employed  in  removing  it  from  irrigable  land. 

Instances  are  recorded  where  sagebrush  has  been  killed  by 
irrigating  the  land  heavily  for  a  season.  The  wetting  of  the  soil 
causes  weeds  and  grass  to  grow  and  when  these  are  dry  they  are 
set  on  fire  and  in  burning  the  dead  sagebrush  is  consumed  at 
the  same  time.  Such  a  practice,  however,  can  not  have  a  wide 
application,  and  where  land  and  water  are  both  valuable,  it  is 
not  a  practice  to  be  recommended. 

Sagebrush  can  be  quite  easily  broken  off  at  the  surface  of  the 
ground,  and  in  clearing  large  tracts,  one  of  the  most  common 
practices  is  to  break  the  brush  by  dragging  a  railroad  rail  over 
it,  using  a  strong  team  at  each  end  of  the  rail.  The  rail  is  dragged 
twice  over,  the  second  time  in  the  opposite  direction  to  the  first. 
Sometimes  if  a  rail  is  not  available,  a  heavy  stick  of  timber  is 
used  as  a  substitute,  but  with  somewhat  less  satisfactory  results. 
Though  the  rails  are  very  commonly  used  straight,  it  is  claimed 
they  are  more  effective  in  tearing  out  and  breaking  off  the  brush 
if  bent  into  a  V  shape.  By  using  a  rail  in  this  way,  nearly  all 

64 


METHODS  OF  PREPARING  LAND 


65 


the  sagebrush  is  broken  off,  and  what  little  remains  can  be  easily 
cut  by  hand  with  a  mattock. 

After  railing,  the  sagebrush  is  either  raked  into  windrows  or 
piled  by  hand  and  burned.  In  districts  where  the  soil  is  subject 
to  blowing  it  is  sometimes  left  in  windrows  30  to  50  feet  apart 
for  a  year  or  two  to  serve  as  a  windbreak  while  the  intervening 
space  is  placed  under  cultivation.  The  cost  of  clearing  land  by 
the  method  of  railing  varies  with  the  density  and  size  of  the  sage- 
brush but  contract  prices  in  the  Northwest  during  recent  years 
have  ranged  from  about  $2.50  to  $3  per  acre  which  includes 
burning  the  brush. 


FIG.  23. — Twin  Falls  sage  brush  grubber. 

Heavy  two-bottom  gang  plows  drawn  by  six  large  mules  have 
been  used  with  success  in  removing  sagebrush  in  the  Yakima 
Valley,  Washington.  This  work  was  done  by  contract  at 
S3  per  acre.  Five  acres  of  plowing  was  an  average  day's  work. 
In  addition  it  cost  SI. 50  per  acre  to  gather  up  and  burn  the  brush ; 
making  the  total  cost  of  clearing  and  breaking  $4.50. 

In  Colorado  sagebrush  has  been  plowed  out  with  a  gang  plow 
and  steam  traction  engine. 


66  USE  OF  WATER  IN  IRRIGATION 

In  southern  Idaho,  at  a  cost  of  $3.50  and  up  for  clearing, 
plowing  and  leveling,  sagebrush  is  cut  by  the  "Twin  Falls 
Grubber/'  Fig.  23.  This  implement  consists  of  heavy  steel 
knives  suspended  from  and  rigidly  attached  to  a  framework 
carried  on  two  wheels.  It  can  be  so  adjusted  that  the  knives 
which  are  set  in  the  form  of  a  V  with  the  point  ahead  can  be 
lowered  a  few  inches  beneath  the  surface  of  the  ground  where  it 
cuts  off  the  roots  of  the  sagebrush.  This  implement  is  not 
adapted  to  stony  land. 

Under  certain  conditions  it  is  often  more  economical  or  satis- 
factory to  remove  the  sagebrush  by  hand  grubbing.  For  this 
work  a  sharp  mattock  is  used  and  the  brush  is  cut  at  the  surface 
of  the  ground.  This  is  most  easily  accomplished  when  the 
ground  is  frozen.  Where  the  growth  is  of  average  size  and 
density,  one  man  can  grub  about  1  acre  a  day.  To  gather  up 
and  burn  the  brush  will  require  possibly  half  a  day  more,  mak- 
ing the  cost  of  clearing  by  hand,  with  wages  at  $2.50  per  day 
about  $3.75  per  acre. 

GREASEWOOD. — This  is  another  shrubby  plant  having  a  wide 
range  of  distribution  from  the  upper  Missouri  River  region  south 
to  Mexico,  and  west  to  the  Sierra  Nevadas  and  Cascade  Moun- 
tains. Its  presence  on  the  plains  is  not  so  general  as  sagebrush. 
It  is  often  found  and  seems  to  thrive  best  on  soils  more  or  less 
impregnated  with  alkali  and  its  presence  for  this  reason  is 
usually  looked  upon  with  suspicion.  A  height  of  8  feet  or  more 
is  sometimes  attained  by  this  plant. 

MESQUITE. — Mesquite  is  found  in  the  far  Southwest  from  cen- 
tral Texas  to  eastern  California.  According  to  its  surroundings 
it  varies  from  straggling  spiny  shrubs  to  a  widely  branched  tree 
50  feet  high  and  3  feet  in  diameter.  The  latter  size  is  attained 
only  in  the  rich  valleys  having  an  abundance  of  moisture.  On 
the  arid  plains,  as  a  shrub  only  2  or  3  feet  high,  the  roots 
may  extend  to  water  at  a  distance  of  60  feet  or  more.  (Bergen 
and  Davis,  Principles  of  Botany,  p.  27.)  Greasewood  and  mes- 
quite  such  as  is  usually  found  on  lands  suitable  for  irrigation  can 
be  cleared  by  the  same  methods  commonly  employed  in  the 
removal  of  sagebrush. 

Large  trees  are  not  commonly  found  in  regions  where  land  is 
prepared  for  irrigation,  but  in  some  localities,  junipers,  pines  or 


METHODS  OF  PREPARING  LAND 


67 


other  trees  of  considerable  size  have  to  be  removed.  As  a  rule, 
all  trees  large  enough  for  wood  or  saw  timber  are  removed  first, 
then  the  smaller  trees  are  slashed,  and  when  dry,  burned  together 
with  the  tops  of  the  larger  trees.  Small  pine  stumps  rot  quickly, 
and  within  a  year  or  two  after  the  cutting  those  4  to  6  inches  in 
diameter  may  often  be  removed  by  a  direct  pull  with  a  good  team. 
For  stumps  of  larger  size,  some  one  of  the  many  types  of  stump 
pullers  is  employed  and  more  or  less  dynamite  and  stump  powder 


FIG.  24. — Blasting  stumps. 

are  used  to  split  or  blow  out  the  ones  too  big  to  be  handled  readily 
with  the  pullers.  The  cost  of  removing  trees  and  stumps  varies 
widely  according  to  the  kind  of  trees  and  the  number  to  the  acre. 
In  clearing  several  thousand  acres  of  pine  land  from  which  the 
saw  timber  and  wood  has  largely  been  removed,  in  the  vicinity 
of  Spokane,  Washington,  the  cost  ranges  from  $25  to  $60  per 
acre.  The  Hercules  stump  puller  is  used  mainly,  and  this  is 
supplemented  by  powder.  In  parts  of  British  Columbia,  where 
land  is  cleared  for  irrigation  without  making  any  use  of  the  wood 


68  USE  OF  WATER  IN  IRRIGATION 

or  saw  timber,  the  cost  per  acre  for  removing  trees  and  stumps 
runs  from  $75  to  $150  per  acre.1  The  tools  used  in  blasting,  the 
manner  of  tamping  the  charge  and  the  best  location  for  the  charge 
are  shown  in  Fig.  24  taken  from  Bull.  134  of  the  Minnesota 
Agri.  Exp.  Sta. 

15.  Preparing  the  Surface  for  Irrigation. — Following  the  re- 
moval of  native  vegetation  land  to  be  irrigated  usually  requires 
grading,  or  smoothing  in  order  that  water  may  be  distributed  or 
spread  over  it  uniformly  with  a  minimun  of  labor  and  expense. 
In  some  parts  of  the  West  large  areas  of  land  are  found  which  are 
naturally  smooth,  and  consequently  require  very  little  grading 
preparatory  to  irrigating,  while  in  other  sections  the  natural 
topography  of  the  land  is  so  irregular  that  the  work  involves  a 
heavy  expense.  There  is  frequently  wide  variation  also  in  the 
requirements  of  different  tracts  in  the  same  locality.  By  level- 
ing or  grading  is  not  meant  the  reduction  of  the  land  to  a  level 
surface  as  this  would  in  most  places  be  not  only  impracticable 
but  undesirable.  Except  where  the  land  is  very  flat,  grading 
as  a  rule  involves  only  the  removal  of  knolls  and  hummocks 
which  interfere  with  the  flow  or  spreading  of  the  water,  and  the 
filling  of  depressions  into  which  the  water  would  collect  to  a 
detrimental  extent.  The  aim  in  grading  should  be  to  obtain 
plane  surfaces.  These,  however,  may  have  little  or  much  slope 
according  to  the  local  conditions  found. 

S.  O.  Jayne,  in  charge  of  the  Irrigation  Investigations  of  the 
Department  of  Agriculture  in  the  State  of  Washington,  states: 
"In  no  instance  should  the  importance  of  securing  a  smooth 
surface  be  underestimated.  Very  often  the  saving  of  the  few 
dollars  needed  to  properly  finish  the  grading  of  a  tract  of  land 
may  mean  an  annual  loss  of  many  dollars  worth  of  time,  water 
and  crops  due  to  the  difficulty  of  irrigation.  Frequently  the 
apparent  smoothness  of  a  piece  of  land  may  lead  to  the  belief 
that  no  grading  is  necessary.  It  is  not  often  however  that 
a  natural  surface  is  found  that  can  not  be  improved  to  some 
extent.  Sometimes,  in  the  rush  of  development  work,  orchards 
or  other  crops  are  planted  before  sufficient  grading  is  done,  with 

1  For  cost  of  clearing  land  in  western  Washington,  see  Eng.  and  Con- 
tracting magazine,  Vol.  XXXVI,  pp.  252,  273,  313,  451,  also  Wash.  State 
Exp.  Sta.  Bui.  No.  101,  also  U.  S.  D.  A.,  B.  P.  I.,  Cir.  No.  25. 


METHODS  OF  PREPARING  LAND  69 

tlu4  idea  that  the  surface  is  good  enough  or  that  this  important 
matter  can  be  deferred  until  some  more  convenient  time.  A 
greater  mistake  than  this  is  seldom  made  in  connection  with 
irrigation  farming." 

If  the  soil  is  fairly  uniform  for  a  considerable  depth,  as  it  is 
in  many  arid  districts  considerable  of  the  surface  layer  may 
be  removed  without  permanently  impairing  the  productivity 
of  the  land.  But  if  coarse  gravel  or  some  other  form  of  un- 
productive subsoil  occurs  within  a  foot  or  two  of  the  surface,  a 
compromise  must  be  made  between  the  advantages  of  good 
grading  and  the  disadvantages  of  poor  soil.  Under  such  con- 
ditions, it  may  sometimes  be  practicable,  in  a  limited  way,  to 
move  the  surface  soil  to  one  side,  remove  so  much  of  the  poor 
subsoil  as  required  and  then  replace  the  surface  soil.  It  may 
be  easier  and  better  to  modify  the  usual  method  of  irrigation 
to  suit  the  land,  than  to  modify  the  land  to  suit  the  usual  method 
of  applying  water.  Grading  is  frequently  carried  too  far  on 


FIG.  25. — Buck-scraper. 

this  kind  of  soil  but  even  under  the  most  unfavorable  conditions 
some  improvement  of  the  surface  is  usually  possible. 

The  cost  of  preparing  the  surface  after  clearing  runs  all  the 
way  from  a  few  cents  to  $50  or  more  per  acre,  depending  mainly 
on  how  much  dirt  has  to  be  moved.  If  the  land  has  not  been 
broken  up  in  removing  the  native  vegetation,  the  first  plowing, 
which  as  a  rule  can  be  done  with  an  ordinary  strong  plow  and 
three  or  four  horses,  will  cost  from  S2  to  82.50.  This,  however, 
is  about  as  far  as  any  itemizing  of  cost  can  be  carried.  In  some 
parts  of  the  West  where  land  is  held  at  $150  to  $300  per  acre,  a 
cost  of  from  $15  to  $30  per  acre  for  grading  is  not  unusual,  nor 
is  it  considered  excessive.  This,  however,  is  higher  than  the 
average  cost  of  such  work. 

If  it  is  necessary  to  move  much  earth  and  the  haul  is  short, 


70  USE  OF  WATER  IN  IRRIGATION 

one  of  the  best  implements  for  the  purpose  is  the  buck-scraper, 
Fig.  25.  In  its  simplest  form  it  consists  of  a  2-inch  plank  with  a 
steel  shoe  on  the  cutting  edge  and  a  tail  board  for  holding  the 
plank  in  position  while  filling,  and  for  controlling  the  angle 
of  it  while  spreading  the  dirt.  Scrapers  of  this  type  have  been 
made  in  lengths  up  to  24  feet  but  the  size  commonly  used  for 
four  horses  is  8  feet  long  and  2  feet  wide.  The  4-horse  size 
is  securely  ironed  and  bolted  together  and  can  be  made  by  the 
local  blacksmith  or  on  the  farm  at  a  cost  of  about  $14.  Some 
scrapers  have  a  lever  attached  to  the  tailboard  so  that  the  scraper 
can  be  set  at  the  desired  angle  in  loading  or  spreading. 

In  parts  of  California  a  modified  buckscraper  or  planer  has 
been  found  especially  useful  on  a  slightly  uneven  ground.  This 
consists  of  a  base  made  of  4  X  12  inch  plank  14  feet  long  and  a 


FIG.  26. — Fresno  scraper. 

back  2  inches  thick,  18  inches  high  and  12  feet  long.  The  base 
and  back  are  held  together  by  the  extension  of  the  steel  plate  with 
which  the  cutting  edge  and  bottom  of  the  base  plane  are  shod  and 
by  iron  straps  on  the  front  side  of  the  upright  plank.  Foot 
boards  are  bolted  across  the  base  plank  which  extends  a  foot 
beyond  the  back  at  each  end.  Four  mules  are  used  at  each  end 
of  the  planer,  the  hitch  being  made  to  the  base  plank  below  the 
footboards.  The  drivers  regulate  the  action  of  the  implement  by 
shifting  their  positions  forward  or  backward  on  the  footboards. 
If  the  grading  is  heavy  and  the  haul  long,  the  "Fresno" 
scraper,  Fig.  26,  is  the  most  satisfactory  implement.  This  is 
a  steel  scraper  4  to  8  feet  long  which  works  on  the  same  prin- 


METHODS  OF  PREPARING  LAND  71 

ciple  as  an  ordinary  "slip."  A  single  steel  handle  about  4 
(Vet  long,  attached  at  the  middle  of  the  back  of  the  scraper 
serves  both  as  a  means  of  regulating  the  dip  in  loading,  and 
of  dumping  and  spreading  the  load.  Usually  a  short  piece  of 
rope  is  attached  to  the  end  of  the  handle  to  facilitate  turning 
the  scraper  back  into  position  preparatory  to  loading.  The 
common  sized  "Fresno"  is  pulled  by  four  horses,  but  a  smaller 
size  suitable  for  two  horses  is  also  made. 

The  scrapers  so  far  described  are  used  for  rapid  movement 
of  earth,  and  are  not  especially  adapted  to  the  work  of  making 
a  finished  surface.  This  is  done  with  some  form  of  rectangular 
leveler,  the  function  of  which  is  analogous  to  that  of  the  long 
"jointer"  plane  used  by  a  carpenter  to  smooth  the  edge  of  a 
board  after  the  prominent  humps  have  been  removed  with  a 
short  "jackplane."  These  levelers  are  made  in  many  sizes  and 
proportions  *to  suit  the  local  requirements,  but  the  principle  of 
their  use  is  for  all  the  same.  The  leveler  is  intended  to  remove 
the  minor  irregularities  of  the  surface  by  spreading  the  earth  left 
in  bunches  by  the  scraper,  and  by  filling  the  slight  depressions 
which  ordinarily  can  not  be  detected  with  the  eye.  After  having 
been  properly  leveled  with  a  leveler  the  field  should  present  a 
smooth  plane  surface. 

The  rectangular  float l  or  "box  leveler, "  Fig.  27,  generally  used 
is  essentially  a  frame  about  6  feet  wide  and  14  to  24  feet  long, 
made  of  2  X  8  inch  or  2  X  10  inch  planks  set  on  edge;  several 
crosspieces  being  used  in  addition  to  the  ones  at  the  ends.  The 
framework  should  be  diagonally  braced  on  top,  and  well  spiked 
or  bolted  together.  The  crosspieces  should  be  faced  on  the 
front  side  with  steel  or  iron  plates.  A  footboard  placed  on  top, 
in  the  middle,  parallel  to  the  long  side  affords  a  place  for  the 
driver  to  stand.  The  hitch  is  made  so  that  the  leveler  is  drawn 
lengthwise  and  the  action  of  the  leveler  can  be  regulated  to  some 
extent  by  the  driver  shifting  his  position  forward  or  back.  The 
number  of  horses  required  varies  with  the  size  and  weight  of  the 
implement.  Four  to  six  are  commonly  used,  but  more  are  some- 
times put  on  very  large  levelers.  In  the  Imperial  Valley,  Cali- 
fornia, rectangular  levelers  have  been  made  in  sizes  up  to  12  X  30 
feet,  requiring  16  horses  and  an  operator  in  addition  to  the 

1  Farmer's  Bulletin  No.  392,  p.  17. 


72  USE  OF  WATER  IN  IRRIGATION 

driver.  A  rectangular  leveler  suitable  for  use  with  two  to  four 
horses  is  a  very  inexpensive  implement  that  can  be*made  on  the 
farm,  and  it  will  often  be  of  value  in  smoothing  plowed  fields  in 
years  succeeding  the  original  grading. 

Graders  or  levelers  of  other  types  are  used  in  some  localities. 
Some  of  these  are  patented  machines.  These  cost  more,  and 
farmers  generally  prefer  the  less  expensive  home-made  ones  which 
are  very  satisfactory. 

When  preparing  the  surface  for  irrigation,  sufficient  soil  to 
allow  for  settling  should  be  placed  in  depressions  of  any  con- 
siderable size,  and  before  the  field  is  seeded  to  permanent  meadow 
or  other  long  term  crops,  it  is  well  to  first  irrigate  it  thoroughly. 


FIG.  27. — Rectangular  float  or  box  leveller. 

The  application  of  water  will  settle  the  soil  of  fills,  and  disclose 
any  need  of  further  grading  more  or  less  of  which  is  usually  re- 
quired to  put  the  surface  in  perfect  shape. 

16.  Furrow  Method  of  Irrigation. — As  a  rule  the  furrow  method 
is  used  to  irrigate  orchards,  small  fruits,  root  crops  and  vegetables. 
It  is  adapted  to  a  wide  variety  of  soils  and  surface  slopes.  Porous 
soils  and  flat  slopes,  however,  should  be  watered,  if  possible,  in 
some  other  way  on  account  of  the  loss  of  water  by  deep  percola- 
tion in  the  former  and  the  sluggish  movement  of  the  small 
streams  in  the  latter.  The  essential  features  of  furrow  irriga- 
tion are  the  head  ditch,  flume  or  pipe  from  which  the  water  is 
distributed,  and  the  furrows.  The  earth  head  ditch  is  still 
common  but  making  openings  in  its  lower  bank  with  a  shovel 


METHODS  OF  PREPARING  LAND  73 

is  being  replaced  by  the  use  of  the  more  stable  and  permanent 
openings. 

EARTHEN  HEAD  DITCHES. — A  skilled  irrigator  may  adjust  ihe 
size  and  depths  of  the  openings  in  a  ditch  bank  so  as  to  secure  a 
fairly  uniform  flow,  but  constant  attention  is  required  in  order  to 
maintain  it.  If  the  water  is  permitted  to  flow  for  half  an  hour 
unattended  the  distribution  is  likely  to  become  unequal.  The 
banks  of  the  ditch  absorb  water  and  become  soft  and  as  the 
water  rushes  through  the  openings,  erosion  enlarges  them,  per- 
mitting larger  discharges  and  lowering  the  general  level  of  the 
water  in  the  ditch  so  that  other  openings  may  have  little  or  no 


FIG.  28. — Home-made  crowder  for  making  head  ditches. 


discharge.  Even  if  it  were  possible  to  divide  the  flow  of  the 
ditch  equally  between  a  certain  number  of  furrows  the  difficulty 
would  not  be  overcome,  because  the  number  of  divisions  would 
invariably  be  too  small.  In  using  such  crude  methods  it  is 
difficult  to  divide  a  stream  of,  say  40  miner's  inches  into  more 
than  about  ten  equal  parts;  but  good  practice  frequently  calls  for 
a  flow  in  each  furrow  of  from  one-fifth  to  three-fourths  of  a  miner's 
inch,  which  can  not  be  secured  by  this  method. 

One  of  the  most  serviceable  home-made  implements  for  making 
head  ditches  is  the  crowder  of  which  several  forms  are  shown 
in  Figs.  5  and  28. 

HEAD  FLUMES. — In  the  Northwest  where  durable  lumber  can 
be  purchased  at  reasonable  rates,  timber  flumes  are  often  used 


74 


USE  OF  WATER  IN  IRRIGATION 


to  distribute  water  to  furrows.  When  installed  for  this  purpose 
they  should  be  but  slightly  elevated  above  the  surface  of  the 
ground  to  prevent  soil  erosion  and  the  scattering  of  the  stream 


FIG.  29. — Common  form  of  wooden  head  flume. 

by  strong  winds.  Flumes  6X6  inches  and  8X8  inches  are 
the  most  common.  The  sides  are  of  1-inch  lumber  but  the  bot- 
toms are  frequently  1  1/4  or  1  1/2  inches  in  thickness.  The  lum- 
ber, preferably  cedar,  is  purchased  in  lengths  of  16  to  18  feet.  Col- 
lars made  of  2  X  4  inch  fir 
i<-2-j**|  joists  for  the  bottom  and  sides 
and  1X4  inches  for  the  tops 
are  placed  around  the  flume 
at  each  joint  and  -midway  be- 
tween joints.  The  water  is 
distributed  to  the  furrows 
through  holes  the  flow  to  each 
being  regulated  by  a  metal 
slide  in  the  manner  shown  in 
Fig.  29. 

Where  suitable  lumber  may 

be  had  for  $15  per  M.  the  cost  of  head  flumes  in  place  of  the 
kind  described  varies  from  $4.50  to  $6  per  100  feet  of  length. 

In  parts  of  the  West  where  lumber  is  costly  head  flumes  were 
formerly  built  of  cement  but  these  in  turn  are  giving  place  to 


FIG.  30. — Concrete  head   flume  with 
opening. 


METHODS  OF  PREPARING  LAND 


75 


concrete  pipes.  By  means  of  a  specially  designed  machine,  which 
is  patented,  cement  mortar  composed  of  one  part  cement  to  about 
six  parts  of  coarse  sand  is  fed  into  a  hopper  and  forced  by  lever 
pressure  into  a  set  of  guide  plates  of  the  form  of  the  flume.  Such 
flumes  are  made  in  place  in  one  continuous  line  across  the  upper 
margin  of  the  orchard  tract.  After  the  flume  is  built  but  before 
the  mortar  has  become  hard,  small  tubes  from  3/4  to  1  1/2  inches 
in  diameter,  the  size  depending  somewhat  on  the  size  of  the  flume, 
are  inserted  in  the  side  next  the  orchard  (Fig.  30).  The  flow 
through  these  tubes  is  regulated  by  zinc  slides.  Flumes  of  this 
kind  are  made  in  five  sizes,  the  smallest  being  6  inches  on  the 
bottom  in  the  clear  and  the  largest  14  inches. 

At  a  slightly  greater  cost  a  stronger  flume  can  be  built  by  the 
use  of  moulds.     The  increased  strength  is  derived  from  a  change 


FIG.  31. — Types  of  concrete  head  flumes. 


in  the  mixture.  In  the  machine-made  flume,  the  mixture  of  one 
part  cement  to  five  or  six  parts  of  sand  is  lacking  in  strength, 
for  the  reason  that  there  is  not  enough  cement  to  fill  all  the  open 
spaces  in  the  sand.  In  using  moulds,  medium-sized  gravel  can 
be  added  to  the  sand  and  the  mixture  resembles  that  of  a  common 
rich  concrete  (Fig.  31). 

PIPES  AND  STANDS. — Head  flumes,  being  placed  on  the  surface 
of  the  ground  interfere  with  the  free  passage  of  teams  in  culti- 
vating, irrigating,  and  harvesting  the  crop.  Dead  leaves  from 
shade  and  fruit  trees  also  clog  the  small  openings  in  the  flumes. 
These  and  other  objections  to  flumes  have  induced  many  fruit 
growers  of  southern  California  to  convey  the  water  in  under- 
ground pipes  and  distribute  it  through  standpipes  placed  at  the 


76 


USE  OF  WATER  IN  IRRIGATION 


head  of  the  rows  of  trees.     Both  cement  and  clay  pipes  are 
used  for  this  purpose. 

This  method  of  distributing  water  to  orchards  is  described 
by  C.  E.  Tait  in  O.  E.  S.  Bulletin  236  from  which  the 
following  illustrations  are  taken.  Fig.  32  shows  a  concrete 
head  pipe  8  inches  in  diameter  laid  with  its  top  12  inches 
below  the  surface  of  the  ground.  The  cut  likewise  shows 
the  larger  stand  with  its  valve  through  which  the  water  is  ad- 
mitted to  the  head  pipe  and  the  smaller  distributing  stand  with 
its  valve  through  which  the  water  flows  to  the  furrows.  The 
methods  used  in  laying  concrete  pipe  and  in  placing  stands  are 
still  further  illustrated  in  Plate  II. 


FIG.  32. — Concrete  head  pipe,  with  stands,  valves,  etc. 

FURROWS. — The  depth,  spacing  and  length  of  furrows  depend  on 
a  variety  of  conditions  pertaining  to  crops,  soils,  and  climate. 
In  growing  shallow-rooted  crops  or  in  irrigating  a  shallow  soil, 
the  furrow  should  likewise  be  shallow  or  of  medium  depth  in 
order  to  moisten  the  soil  around  the  roots  and  lessen  the  loss  by 
deep  percolation.  However,  in  growing  such  crops,  it  is  well  to 
bear  in  mind  that  a  large  part  of  the  upper  12  inches  of  soil  in 
an  arid  climate  can  not  be  utilized  for  the  nourishment  of  plants 
for  the  reason  that  the  heavy  evaporation  robs  it  of  its  available 
moisture. 

In  all  cultivated  crops  the  grower  should  figure  on  reserving 


PLATE  II 


I 

bC 
G 

I 


METHODS  OF  PREPARING  LAND 


77 


a  certain  depth  of  the  top  soil  to  be  used  as  a  sort  of  blanket  or 
dry  soil  mulch  covering  to  protect  the  moist  soil  beneath.  It  is 
unfortunate  that  the  soil  so  reserved  is  the  most  fertile,  the  best 
aerated,  and  the  most  easily  worked  soil  of  the  field.  In  the  ex- 
periments conducted  by  Dr.  Loughridge  of  the  University  of 
California  and  the  writer  in  1905  in  the  citrus  orchards  of  River- 
side, California,  it  was  shown  that  irrigation  by  means  of  a  large 
number  of  shallow  furrows  followed  by  shallow  cultivation  was 
not  good  practice  for  that  particular  product,  soil  and  climate. 
During  the  dry  hot  months  of  summer  little  free  moisture  was 
found  in  the  upper  12  inches  of  soil  prior  to  the  time  of  irrigating. 
In  other  words  the  moisture  content  of  the  top  foot  of  soil  was 
wholly  inadequate  to  support  plant  life.  As  a  result  the  tree 
roots  found  in  this  layer  of  soil  were  either  withered  or  unable 


2Ft.       iFt. 


2Ti.         IFt.        0             1             2 

li| 

• 

ill 

fi 

^-^ 

^.^ 

FIG.  33. — (a)  Distribution  of  water  from  deep  furrow,     (b)  From  shallow 
furrow,  in  same  time. 

to  perform  their  proper  function.  Orchardists  who  permitted 
the  roots  of  trees  to  be  lured  near  the  surface  during  the  winter 
rains  were  disappointed  in  learning  that  the  trees  after  expend- 
ing a  part  of  their  vital  force  in  developing  roots  to  occupy  this 
new  feeding  zone  were  damaged  by  the  subsequent  withering  or 
inaction  of  part  of  the  root  system  so  formed.  Modern  practice 
in  orchard  irrigation  in  southern  California  aims  to  prevent 
by  frequent  and  deep  cultivation  the  formation  of  roots  near  the 
surface.  This  results,  as  has  been  stated,  in  setting  aside  the  top 
layer  of  soil  in  order  to  conserve  and  make  more  constant  the 
moisture  content  of  the  remainder.  The  depth  of  this  top  layer 
varies  with  different  conditions.  A  depth  which  would  suffice 
for  the  low  temperature  and  light  evaporation  of  the  Bitterroot 
Valley,  Montana,  might  have  to  be  increased  100  per  cent,  in 


78  USE  OF  WATER  IN  IRRIGATION 

Santa  Ana  Valley,  California  or  the  Salt  River  Valley  in  Arizona. 
The  same  principles  however,  apply  to  all  three  localities. 

From  the  foregoing  it  is  observed  that  the  top  layer  of  dry 
soil  mulch  should  not  be  irrigated.  This  can  be  accomplished 
in  part  at  least  by  the  use  of  deep  furrows.  Fig.  33a  shows  the 
distribution  of  the  water  in  7  hours  from  a  furrow  10  inches  deep 
and  Fig.  33b  a  similar  distribution  from  a  furrow  5  inches  deep 
in  the  same  time.  From  the  former  it  will  be  seen  that  little  of 
the  mulch  is  moistened  and  that  the  water  has  a  wide  distribu- 
tion at  a  depth  of  2  feet  below  the  surface  where  the  most  roots 


FIG.  34. — Orchard  irrigation  showing  deep  furrows. 

are  to  be  found,  whereas  in  the  latter  nearly  one-half  of  the 
water  applied  has  found  its  way  into  the  soil  mulch  to  be  speedily 
dissipated  by  evaporation.  According  to  the  present  practice  in 
citrus  irrigation,  four  to  six  furrows  are  made  between  the  rows 
in  the  heavier  soils  and  two  to  four  in  the  lighter  soils.  These 
furrows  are  made  8  to  9  inches  deep  and  are  made  by  attaching 
lister  plows  to  the  frames  of  wheeled  cultivators.  Such  furrows 
are  shown  in  Fig.  34. 

LENGTH  AND  LOCATION  OF  FURROWS. — In  porous  soils  it  is  often 
found  necessary  to  limit  the  length  of  furrows  to  200  feet.     Even 


METHODS  OF  PREPARING  LAND 


79 


in  reasonably  tight  soils  it  is  seldom  wise  to  exceed  a  length  of 
GOO  feet.     These  limitations  as  to  length  are  made  for  the  pur- 
pose of  securing  a  more  even    __  fc 
distribution     of    the 
The  main  defects  of 


water. 

a  long 

furrow  one-eighth  to  one- 
quarter  of  a  mile  in  length  are 
the  over-irrigation  of  the  sub- 
soil near  the  head  ditch  or 
flume  if  the  soil  is  porous  and 
the  flooding  of  the  lower  por- 
tion of  the  field  if  the  soil  is 
impervious.  A  good  arrangement 
divide  a  40-acre  tract  into  three 


(  ) 


FIG. 


35. — Furrow   irrigation   showing 
dry  spaces. 


in    medium 
belts    by   as 


soils 
many 


is    to 
head 


FIG.  36. — Plan  for  laying  out  zigzag  furrows. 


ditches,    thus   making    the   furrows   in   each    belt   or  field  440 
feet  long. 


80  USE  OF  WATER  IN  IRRIGATION 

In  irrigating  small  fruits,  roots,  vegetables,  and  to  some  ex- 
tent orchards  by  the  furrow  method,  the  furrows  are  made 
parallel  to  the  rows.  In  the  case  of  mature  orchards,  however, 
cross-furrowing  is  gaining  in  popular  favor.  The  purpose  of  this 
modification  is  to  moisten  the  dry  spaces  shown  in  Fig.  35.  Each 
space  in  mature  orchards  may  contain  from  100  to  150  square 
feet  which  usually  becomes  so  dry  that  it  is  worthless  as  a  feed- 
ing ground  for  rqots.  In  order  to  moisten  these  dry  spots,  first, 
cross-furrows,  indicated  by  the  dotted  lines  in  Fig.  36,  are  made, 
then  the  regular  furrows  are  made  after  which  the  zigzag  system 
as  shown  is  completed  by  a  little  hand  work  with  a  shovel. 
Since  the  flow  in  each  furrow  can  be  quite  accurately  gauged  by 
the  slide  on  the  stand,  it  is  customary  to  turn  in  more  water  to 
the  furrows  which  feed  the  cross  furrows. 

Cross  furrowing  is  sometimes  resorted  to  on  steep  slopes  to 
lessen  the  velocity  of  the  water  and  thus  prevent  erosion.  It  is 
also  made  use  of  on  the  lower  portions  of  orchard  tracts  to  secure 
as  deep  a  penetration  of  moisture  as  occurs  from  the  direct 
furrows  on  the  upper  portions.  On  very  steep  slopes,  the  rows 
of  orchard  trees  are  planted  on  grade  lines,  the  fall  being  3  to  4 
inches  per  100  feet  in  ordinary  soils.  In  such  cases  the  furrows 
are  made  parallel  to  and  on  the  same  grade  as  the  tree  rows. 

17.  Corrugation  Method  of  Irrigation. — This  is  a  modified 
form  of  furrow  irrigation  and  is  quite  extensively  practised  in  the 
states  of  Idaho  and  Washington.  It  is  adapted  to  a  rather  wide 
range  of  topography,  soils  and  crops,  but  the  most  favorable 
conditions  for  its  use  are  a  rather  steep  slope  and  medium  soils 
as  regards  sand  and  clay.  The  reasons  for  these  requirements  are 
readily  explained.  Considerable  slope  to  the  field  is  necessary 
in  order  to  create  motion  in  the  small  quantity  of  water  which 
flows  in  each  corrugation.  Again,  in  coarse  porous  soils  there  is 
too  heavy  a  loss  due  to  deep  percolation  and  in  heavy  clay  soils 
too  many  corrugations  and  too  much  time  are  needed  in  order 
to  moisten  the  entire  top  layer  of  soil. 

HEAD  DITCHES. — For  average  fields  of  about  10  acres  in  extent 
the  head  ditch  is  made  about  2  feet  wide  at  the  water  line.  A 
light  grade  with  a  correspondingly  low  velocity  is  preferable 
in  order  to  check  and  control  the  flow  with  greater  ease.  A  grade 
ranging  from  0.05  to  0.25  per  cent,  may  be  used,  but  about  0.1 5  per 


METHODS  OF  PREPARING  LAND 


81 


cent,  is  ideal  for  average  soils.  After  the  grade  stakes  are  set  a 
dead  furrow  is  plowed  along  the  line.  This  can  be  cleaned  out 
with  the  ordinary  "A"  ditcher  after  which  one  or  more  furrows 
is  plowed  along  the  bottom  throwing  the  dirt  down  hill.  The 
"A"  ditcher  is  again  run  through  twice.  With  the  exception  of 
a  little  hand  work  the  head  ditch  is  then  completed. 

CORRUGATIONS. — The  size  of  the  corrugations  depends  on  the 
character  of  the  soil,  kind  of  crop,  and  length  of  run.  In  sandy 
soils  liable  to  cave  in  or  erode  the  corrugations  are  made  larger 
than  hi  clay  soils.  In  perennial  crops  such  as  alfalfa  or  clover 
they  are  also  made  larger  than  for  annual  crops  since  the  cutting 
and  harvesting  of  hay  crops  tend  to  fill  up  the  corrugations.  As 
regards  the  length  of  the  run  it  is  never  advisable  to  exceed  one- 
eighth  of  a  mile  (660  feet).  An  excellent  arrangement  under 
normal  conditions  is  to  divide  a  40-acre  field  into  three  runs  of 
440  feet  each. 


FIG.  37. — Furrower  designed  by  Don  H.  Bark. 

The  distance  between  the  corrugations  is  determined  by  the 
texture  of  the  soil  and  the  action  of  capillarity  in  conducting 
moisture  from  wet  to  dry  soils.  When  this  action,  which  is 
called  "subbing"  by  the  irrigator,  is  unimpeded  the  distance  may 
be  as  great  as  4  feet  or  more  but  in  the  more  impervious  soils  it 
is  frequently  18  inches  or  less.  The  spacing  of  the  corrugations 
in  southern  Idaho  is  2  1/2  to  3  feet.  A  safe  rule  to  follow  is  to 
space  the  corrugations  so  that  a  small  stream  running  in  each  for 
12  to  24  hours  will  moisten  all  the  intervening  soil. 

The  best  field  slope  for  this  method  of  irrigation  is  a  fall  of  1 
foot  in  every  hundred  feet  but  by  decreasing  the  flow  so  as  to 
avoid  erosion  slopes  as  steep  as  15  to  20  feet  per  hundred  feet 
may  be  successfully  watered.  Fields  are  corrugated  or  furrowed 


82 


USE  OF  WATER  IN  IRRIGATION 


after  seeding  but  before  the  seed  has  sprouted.  An  implement 
resembling  the  front  runner  of  a  bob  sled,  Fig.  37,  designed  by 
Don  H.  Bark  is  now  much  used  for  this  purpose  in  both  Wyoming 
and  Idaho. 

HEAD  DITCH  DISTRIBUTARIES. — Small  tubes  16  to  24  inches  in 
length  made  of  four  pieces  of  lath  inserted  in  the  lower  bank  of 
the  head  ditch  serve  to  regulate  the  flow  in  each  corrugation. 
All  tubes  between  checks  are  puddled  in  at  the  same  level  and 
at  the  same  distance  below  the  water  line  so  as  to  equalize  the 
discharge  through  each.  Small  metal  tubes  are  also  used  for  the 
same  purpose  but  they  are  more  expensive  and  wash  out  more 
readily.  Others  use  small  syphons  of  rubber  hose  or  pipe  which 


FIG.  38. — Check  box  for  corrugation  method  of  irrigation, 


are  transferred  from  place  to  place  as  needed  but  the  trouble  met 
with  in  setting  each  syphon  is  a  serious  objection  to  this  device. 
At  other  times  diversions  are  made  from  a  small  temporary  and 
supplemental  ditch  extending  for  100  feet  or  so  parallel  to  the 
main  head  ditch. 

CHECKS. — The  surface  of  the  water  in  the  head  ditch  is  held 
from  1  to  2  inches  above  the  top  of  the  spouts  by  means  of 
checks.  These  are  spaced  at  long  or  short  intervals  depending 
on  the  grade  of  the  ditch  and  the  kind  of  check  used.  When 
canvas  dams  are  inserted  they  are  placed  far  enough  apart  so 
that  there  will  be  a  fall  of  about  6  inches  between  every  two. 


METHODS  OF  PREPARING  LAND  83 

If  wooden  chocks  (Fig.  38)  are  used  the  fall  may  be  6  to  10 
inches. 

HEAD  OF  WATER. — The  most  suitable  head  of  water  for  this 
method  of  irrigation  varies  from  1  to  2  second-feet.  Each  second- 
foot  is  distributed  among  40  to  120  corrugations,  the  largest 
number  being  used  on  the  steeper  grades. 

18.  Flooding  Methods  of  Irrigation. — It  is  impossible  to  state 
with  any  degree  of  certainty  which  method  of  flooding  was  first  put 
into  practice  but  it  may  readily  be  assumed  that  the  "wild"  or 
"mountain"  method  was  one  of  the  earliest  methods  due,  no 
doubt,  to  the  low  initial  cost  of  putting  water  upon  the  land. 
Under  this  method  practically  the  entire  cost  of  preparing  the 
land  for  irrigation  is  expended  in  the  building  of  laterals  and  but 
little  money  is  spent  in  leveling  or  preparing  the  land. 

The  laterals  may  be  located  in  one  of  three  ways,  namely: 
(1)  On  contours,  (2)  down  the  steepest  slope,  or  (3)  diagonally 
down  the  slope. 

1.  The  laterals  are  built  approximately  along  contours  and  are 
given  just  enough  slope  to  produce  the  desired  velocity  of  flow. 
Irrigation  is  accomplished  by  turning  the  water  out  at  intervals 
along  the  lateral  and  allowing  it  to  flow  down  the  slope  to  the 
next  lower  lateral.     This  method  is  usually  employed  on  very 
steep  slopes. 

2.  Laterals  are  built  directly  down  the  slope,  the  grade  of  the 
lateral  approximating  that  of  the  slope,  and  usually  no  attempt  is 
made  to  reduce  the  velocity  of  the  water.     The  water  is  turned 
out  at  intervals  along  the  lateral  and  the  flooding  is  accomplished 
by  the  water  flowing  simultaneously  laterally  and  down  the 
slope.     This  method  can  not  be  employed  on  very  steep  slopes  as 
the  water  will  have  a  tendency  to  follow  alongside  the  lateral  and 
produce  serious  washing  of  the  soil  and  will  not  spread  out 
laterally  to  any  appreciable  extent. 

3.  Laterals  built  diagonally  down  the  slope  have  a  tendency  to 
approach  a  mean  between  the  two  methods  mentioned  above. 
Such  a  lateral  has  a  steeper  grade  than  that  of   the   contour 
lateral  and  a  lighter  grade  than  that  of  the  second  method,  thus 
the  velocity  of  the  water  in  the  lateral  is  increased  over  that 
in  the  first  and  decreased  under  that  of  the  second  case.     With 
this  method  water  can  be  run  a  slightly  greater  distance  than  by 


84  USE  OF  WATER  IN  IRRIGATION 

either  of  the  first  two  methods  mentioned  before  it  must  be 
changed. 

There  are  two  distinct  methods  employed  in  irrigating  by  wild 
flooding,  each  of  which  has  its  advantages  and  disadvantages. 
One  method  is  to  begin  to  irrigate  with  the  lowest  lateral  and 
work  up  the  hill.  The  advantage  of  this  method  is  that  there  is 
always  dry  land  upon  which  the  irrigator  can  cross  from  one 
part  of  the  field  to  another.  The  disadvantage  is  that  all  waste 
water  recovered  by  a  lower  lateral  must  be  turned  upon  land  that 
has  already  been  irrigated.  The  other  method  is  to  begin  with 
the  upper  lateral  and  work  down  the  slope.  This  method  has 
the  advantage  that  all  waste  water  can  be  collected  in  a  lower 
lateral  and  turned  upon  land  that  has  yet  to  be  irrigated.  The 
disadvantage  is  that  the  irrigator  has  more  or  less  wet  ground 
where  he  is  at  work  changing  the  water. 

The  spacing  of  the  laterals  varies  with  the  degree  of  steep- 
ness of  the  land,  the  smoothness  of  the  surface,  the  physical 
properties  of  the  soil,  the  amount  or  head  of  water  to  be  used, 
and  the  crop  to  be  irrigated. 

The  initial  cost  of  wild  flooding  is  less  than  that  of  any  of  the 
other  methods  yet  this  is  more  than  offset  by  the  increased  cost 
of  handling  the  water  upon  the  ground.  The  water  requires 
more  attention  and  more  leading  around  with  the  shovel  in 
order  to  cover  all  of  the  surface  and  must  be  changed  at  more 
frequent  intervals.  In  addition  this  method  can  not  be  classed 
as  an  economical  method  as  the  water  runs  quickly  over  the  sur- 
face and  penetrates  but  slightly  into  the  soil,  it  can  not  be  dis- 
tributed evenly  over  the  land,  and  more  or  less  water  runs  off  the 
field  and  is  lost. 

19.  Surface  Pipe  Method  of  Irrigation. — This  method  is  an 
outgrowth  of  irrigation  by  pumping.  It  requires  no  ditches, 
check,  or  border  levees  nor  is  it  essential  that  the  surface  be 
graded  to  a  uniform  slope.  For  these  reasons  it  is  rapidly  gaining 
in  favor  in  the  East  and  is  destined  to  become  one  of  the  most 
common  methods  of  applying  water  under  humid  conditions. 
When  irrigation  is  practised  to  supplement  the  natural  rainfall 
during  dry  spells,  relatively  small  quantities  are  needed.  An 
application  of  2  acre-inches  per  acre  is  usually  sufficient  at  any 


METHODS  OF  PREPARING  LAND 


85 


one  time.  Accordingly  pipe  mains  ranging  in  size  from  6  to  12 
indies  in  diameter  convey  sufficient  pumped  water  to  the  highest 
portions  of  the  fields  from  which  it  is  distributed  through  mov- 
able surface  pipes  attached  to  special  hydrants  or  stands  on  the 
head  mains.  All  main  and  head  pipes  are  laid  far  enough  below 
the  surface  so  as  not  to  interfere  with  the  plow  or  subsoiler. 
When  a  field  has  been  watered  and  the  surface  pipes  removed, 
nothing  remains  to  interfere  with  the  ordinary  processes  of 
growing  and  harvesting  crops  until  a  second  watering  is  needed. 
To  be  free  from  the  inconvenience  of  an  open  ditch,  levee,  or 
other  field  obstruction  and  to  be  able  to  utilize  the  space  which 
these  occupy,  are  strong  incentives  to  adopt  this  method.  It  is 
also  well  adapted  to  the  irrigation  of  the  rolling  and  irregular  land 
surfaces  of  the  Atlantic  Coast  States.  As  will  be  noted  later 
the  surface  of  fields  should  be  carefully  graded  and  smoothed 


FIG.  39. — Stand  and  valve  for  irrigating  alfalfa. 


as  a  necessary  preparation  but  only  to  a  limited  extent  can  this 
be  done  in  the  far  East  where  the  soil  is  too  shallow  to  permit 
much  surface  grading. 

This  method  as  used  in  southern  California  for  the  irriga- 
tion of  alfalfa  is  described  by  C.  E.  Tait  in  Bull.  236  of  the 
Office  of  Experiment  Stations,  U.  S.  D.  A.,  issued  in  1912.  Since 
then  a  number  of  improvements  have  been  made  to  which  the 
author  of  this  publication  has  called  the  writer's  attention. 
The  concrete  head  pipes  for  alfalfa  are  usually  12  inches  in  di- 
ameter and  are  laid  beneath  the  surface.  About  100  feet  apart, 
stands  of  the  same  material  are  inserted  in  the  head  pipe  and 
at  the  top  of  each  stand  a  valve  is  placed  as  shown  in  Fig.  39. 
The  prices  of  alfalfa  valves  as  made  by  the  Irrigator's  Supply 
Company  of  Ontario,  California,  follow: 


86 


USE  OF  WATER  IN  IRRIGATION 


Size  of   pipe, 

Size  of  opening, 

Weight, 

Pn'pp 

inches 

inches 

pounds 

±  lie" 

10 

7  1/2 

7  1/2 

$1.65 

12 

9  1/2 

10  1/2 

2.25 

14 

11  1/2 

16 

2.75 

16 

13  1/2 

22 

3.50 

18 

15  1/2 

29 

5.50 

Standpipes  which  project  a  foot  or  two  above  the  surface  are 
seldom  used  in  irrigating  alfalfa.  The  more  usual  practice  is 
to  use  only  a  portion  of  a  joint  of  pipe  for  stands  which  terminate 
4  to  6  inches  below  the  ground  surface.  When  the  valve  is  pro- 
tected by  a  covering  of  earth  when  not  in  use,  wagons  and  other 
implements  can  pass  over  it  without  injuring  it. 

Hose  and  hose  connections  between  the  stands  and  the  sur- 
face pipes  have  also  been  substituted  for  metal  pipes  and  metal 
elbows.  The  detachable  surface  pipe  is  made  of  galvanized  iron, 
usually  24  gauge.  It  is  8  inches  in  diameter  and  is  made  up  in 

Taper  20  Gage.     Reinforcing  Ring 


FIG.  40. — Surface  pipe  for  irrigating  from  stands. 

10-foot  lengths.  Each  length  consists  of  a  single  sheet  of  metal 
which  is  rolled,  crimped,  and  soldered  in  the  manner  shown  in 
Fig.  40.  The  socket  end  of  each  length  is  reinforced  by  a  ring 
and  the  spigot  end  is  formed  by  riveting  a  tapering  joint  8  inches 
long  of  20  gauge. 

Mr.  Tait  states  that  with  a  head  of  60  miner's  inches  (1  1/5 
second-feet)  one  man  can  irrigate  2  1/2  acres  in  a  10-hour  day. 
In  irrigating  a  field  the  water  is  used  from  one  stand  for  a 
strip  equal  in  width  to  the  distance  between  stands  and  in  length 
from  the  head  to  the  foot  of  the  field.  If  one  begins  to  irri- 
gate at  the  upper  end,  he  proceeds  toward  the  lower  end  by  gradu- 
ally adding  sections  of  pipe  until  the  entire  strip  is  watered. 

Where  the  depth  and  fertility  of  the  soil  and  other  conditions 
will  permit,  it  pays  to  grade  alfalfa  fields  with  as  much  care 
for  this  method  as  for  any  other.  If  the  surface  is  left  rough 


METHODS  OF  PREPARING  LAND  87 

and  uneven  the  water  can  not  be  evenly  distributed,  causing  dry 
spots  on  the  high  places  and  over-irrigation  and  scalding  in  the 
low  places. 

20.  Border  Method  of  Irrigation. — The  border  method  is  well 
adapted  to  the  irrigation  of  alfalfa  and  grain  crops  and  is  used 
extensively  in  California  and  Arizona  and  to  a  less  extent  in 
Idaho,  Montana  and  other  Rocky  Mountain  States.  It  consists 
of  dividing  the  field  into  a  series  of  parallel  strips  or  borders  by 
low  flat  levees.  It  is  especially  adapted  to  land  with  a  medium, 
uniform  slope  and  to  light  open  soils  that  absorb  water  readily. 
It  can  also  be  used  best  under  canals  which  deliver  water  to  users 
in  large  heads. 


/\ 


FIG.  41. — Home-made  levee  planer  or  smoother. 

In  preparing  the  land  for  border  irrigation,  the  ground  is  first 
plowed  or  disked  and  the  location  of  the  levees  is  marked  by  plow 
furrows.  A  good  foundation  for  the  levees  is  made  by  plowing 
two  or  more  furrows  on  each  side  of  the  levee  line,  the  earth 
being  thrown  toward  the  center  from  either  side.  The  levees  are 
built  with  a  Fresno  scraper  which  is  driven  back  and  forth  at 
right  angles  to  the  levee  lines,  the  earth  which  is  skimmed  from 
the  surface  being  dumped  on  the  levee  line  so  that  the  loads 
overlap  one  another.  The  levees  after  being  roughly  made  by 
the  scrapers  are  brought  down  to  grade  and  smoothed  by  an 
implement  known  as  a  planer  or  smoother,  Fig.  41.  The  levees 


88 


USE  OF  WATER  IN  IRRIGATION 


should  be  made  so  that  after  being  smoothed  and  settled  by 
water,  they  will  be  from  8  to  10  inches  high  in  the  center  and 
have  a  base  of  6  to  8  feet.  This  will  permit  the  cutting  and  raking 
of  hay  with  comparative  ease.  The  cost  of  preparing  border 
checks,  including  ditches  and  gates,  ranges  from  $10  to  $30  per 
acre. 

The  levees  usually  extend  in  the  direction  of  the  steepest  slope. 
When  the  slope  is  too  steep  the  borders  are  laid  off  diagonally 
across  the  face  of  the  slope.  A  medium  loam  soil  with  an  even 
grade  of  about  1  foot  in  400  feet  presents  ideal  conditions  for 
the  border  method.  For  these  conditions  border  checks  50  feet 
wide  and  from  600  to  800  feet  long  will  be  found  desirable. 
Where  the  grade  is  steeper  than  1  foot  in  400  feet,  the  checks 
should  be  30  to  40  feet  in  width.  If  the  fall  is  less  than  that 


FIG.  42. — Border  gate  of  wood  used  in  Sacramento  Valley,  Cal. 

described,  the  checks  can  be  made  wider  and  longer.  In  most 
cases  it  will  not  be  found  advisable  to  make  checks  longer  than 
1320  feet  or  wider  than  100  feet.  Border  checks  should  be  level 
in  cross  section  to  irrigate  well  and  it  is  a  good  plan  to  make  the 
first  25  or  50  feet  of  the  upper  end  of  the  check  level  in  both 
directions.  This  causes  the  water  to  spread  evenly  between  the 
levees  when  leaving  the  head  ditch,  thus  allowing  it  to  flow  down 
the  check  in  a  thin  sheet. 

The  head  or  feed  ditch  should  be  located  so  that  two  or  more 
border  checks  can  be  watered  at  the  same  time.  The  size  of  the 
ditch  will  naturally  depend  upon  the  grade  that  can  be  secured 
and  the  quantity  of  water  to  be  carried.  For  ordinary  farms  of 
10  to  40  acres,  the  feed  ditch  should  be  at  least  4  feet  wide  on  the 
bottom  and  excavated  about  1  foot  below  the  ground  surface, 
the  banks  being  about  2  feet  high. 


METHODS  OF  PREPARING  LAND  89 

\Yator  is  admitted  to  each  check  through  a  gate  or  box  placed 
in  the  ditch  bank.  Fig.  42  shows  a  type  of  timber  gate  used 
extensively  in  the  Sacramento  Valley,  California.  Another 
more  substantial  gate  built  of  concrete  is  shown  in  Fig.  43. 
The  ordinary  head  of  water  turned  into  each  check  usually  varies 
from  1  to  5  cubic  feet  per  second.  The  advantage  of  the  larger 
head  is  that  the  land  can  be  covered  more  quickly  and  the  cost 
of  applying  water  is  materially  reduced.  Water  after  being 
admitted  passes  over  the  check  in  a  thin  sheet  and  before  reaching 
the  lower  end  of  the  field,  the  check  gate  is  closed,  since  there  is 
then  usually  enough  water  flowing  in  the  check  to  complete  the 
irrigation.  A  drainage  ditch  is  generally  provided  at  the  lower 


FIG.  43. — Border  gate  of  concrete  used  in  Sacramento  Valley,  Cal. 

end  of  the  checks  to  carry  off  surplus  water.  The  average  cost 
of  applying  water  each  time  ranges  from  10  to  25  cents  per  acre. 
Ralph  D.  Robertson,  irrigation  engineer  of  the  U.  S.  Depart- 
ment of  Agriculture,  who  has  had  much  to  do  with  irrigation 
development  in  the  Sacramento  and  San  Joaquin  valleys, 
California,  is  of  the  opinion  that  the  sketch  shown  in  Fig.  44 
typifies  the  best  practice  of  the  border  method  as  used  in  the 
Sacramento  Valley.  In  this  field  the  checks  are  50  feet  wide 
and  800  feet  long.  The  levees  are  8  feet  wide  on  the  bottom  and 
10  inches  high.  The  slope  is  1  foot  in  400  feet,  there  being  a 
difference  of  elevation  of  2  feet  between  the  upper  and  lower 


90 


USE  OF  WATER  IN  IRRIGATION 


end  of  each  check.  The  soil  is  a  silt  loam  and  the  cost  of  prepara- 
tion was  $15  per  acre.  The  head  ditch  is  5t  feet  wide  on  the 
bottom,  2  feet  deep,  and  has  a  capacity  of  10  cubic  feet  per 
second.  The  following  brief  descriptions  give  some  idea  of  the 
border  method  as  practised  in  other  localities. 

Under  the  Sutter  Butte  canal  in  the  Sacramento  Valley, 
California,  the  feed  ditches  are  designed  to  carry  from  10  to 
15  cubic  feet  per  second  and  irrigation  progresses  at  the  rate  of 

Feed  Ditch ,5  Feet  Wide,  Capacity,  10  Sec.  Ft. 


JDrain  Ditch 

FIG.  44. — Alfalfa  field  near  Gridley,  Cal.,  irrigated  by    border    method. 

2  acres  per  hour  with  two  men  handling  the  water.  Usually 
from  2.5  to  5  cubic  feet  per  second  are  turned  into  each  check. 
The  cost  of  each  watering  is  about  20  cents  per  acre.  When  irri- 
gation was  first  practised  in  the  Turlock  and  Modesto  districts, 
California,  the  land  was  prepared  in  rectangular  and  contour 
checks.  Of  late  years  the  border  method  has  grown  in  favor. 
The  time  allowed  the  irrigator  in  these  districts  for  a  head  of  water 
of  10  to  15  cubic  feet  per  second  varies  during  the  season  from  20 


METHODS  OF  PREPARING  LAND  91 

to  30  minutes  per  acre.  The  average  cost  of  applying  water  for 
the  season  is  about  50  cents  per  acre.  In  Yolo  County,  Cali- 
fornia, where  tho  border  method  originated,  a  common  head  of 
water  delivered  to  the  irrigator  is  from  10  to  12  cubic  feet  per 
-cc(  md.  Average  checks  having  a  fall  of  1  foot  in  400  feet  are 
made  50  feet  wide  and  1320  feet  long.  The  cost  of  applying 
water  is  from  10  to  20  cents  per  acre  for  each  irrigation.  In 
the  Imperial  Valley,  California,  the  cost  of  preparing  border 
checks,  ditches  and  gates  is  from  $5  to  $20  an  acre  and  where 
much  native  vegetation  has  to  be  removed,  the  cost  may  reach 
$40  per  acre.  The  checks  vary  from  50  to  75  feet  in  width  and  in 
length  up  to  1320  feet.  Two  cubic  feet  per  second  represent  the 
average  head  turned  into  each  check.  In  Salt  River  Valley, 
Arizona,  borders  are  made  from  30  to  50  feet  wide  and  from 
1/8  to  1/4  mile  long.  A  head  of  water  of  about  100  miner's 
inches  is  turned  into  a  check  30  feet  wide  and  660  feet  long 
requiring  from  1  to  3  hours  to  complete  an  irrigation. 

21.  Check  Method  of  Irrigation. — This  method  consists  of 
dividing  the  field  into  a  number  of  small  compartments  sur- 
rounded by  low  levees.  Provision  is  usually  made  to  flood  each 
check  by  means  of  a  gate  or  box  placed  in  the  ditch  bank.  This 
method  is  well  adapted  to  light  sandy  soils  having  a  rather 
uniform  slope  of  3  to  15  feet  to  the  mile,  but  is  used  also  in  heavy 
soils  where  it  is  necessary  to  hold  water  in  the  checks  to  secure 
its  percolation  downward.  There  are  various  modifications  of 
the  check  system  in  use.  When  the  levees  follow  the  natural 
contour  of  the  ground  surface,  the  enclosed  spaces  are  called 
contour  checks.  Fig.  45  shows  a  40-acre  field  prepared  by  the 
contour  method  in  which  the  single  lines  represent  the  levees 
built  on  the  contours  and  the  double  lines,  the  field  ditches. 
Cross  levees  are  constructed  to  break  up  some  of  the  larger 
checks,  making  the  average  size  of  each  compartment  1  acre 
or  less  in  extent. 

Before  the  checks  can  be  formed,  it  is  necessary  to  make  a 
survey  to  determine  the  location  of  the  levee  lines  and  the  field 
ditches.  Engineers  follow  somewhat  different  methods  of  con- 
ducting a  survey  of  this  kind  but  the  general  operation  and  the 
end  attained  are  the  same.  A  party  of  three  consisting  of  a 
levelman,  rodman,  and  a  man  following  with  a  plow  can  work 


92 


USE  OF  WATER  IN  IRRIGATION 


to  advantage.  The  levelman  sets  up  his  instrument  where  he 
can  command  a  good  view  of  the  field  and  takes  a  number  of  ran- 
dom readings  at  different  points  to  gain  a  general  knowledge  of 
the  topography.  He  then  selects  a  point  on  the  highest  contour 
and  takes  a  reading  on  a  hub  or  stake  driven  flush  with  the 
ground.  This  stake  may  be  referenced,  to  be  used  as  a  bench- 
mark for  future  surveys.  The  levelman  after  noting  the  rod 
reading  calls  this  the  grade  rod  and  locates  points  of  the  same 
elevation  by  having  the  rodman  proceed  over  the  field  with  the 
target  set  at  the  initial  reading.  The  rodman  marks. each  point 
with  a  stake  and  the  plowman  follows  closely  behind  connecting 
up  each  point  with  a  furrow  which  marks  the  location  of  the 
levees.  When  the  rodman  has  reached  the  end  of  the  field,  he 


-Feed  Ditch 


Ditch 


FIG.  45. — Forty-acre  field  showing 
contour  checks. 


FIG.  46. — Rectangular  checks  on 
field  shown  in  Fig.  45. 


moves  the  target  up  the  correct  distance  from  the  contour  in- 
terval decided  upon  and  starts  across  the  field  a  second  time, 
locating  the  new  contour  line,  the  plowman  following  as  before. 
Three  or  4  inches  is  the  usual  vertical  distance  between 
contours  and  it  will  not  be  found  advisable  to  contour  land 
that  slopes  more  than  2  feet  in  100  feet.  The  height 
of  the  levees  depends  upon  the  difference  in  elevation  of  the 
contour  lines  and  the  depth  of  water  applied  in  one  irrigation. 
As  a  rule  levees  8  or  9  inches  high  after  being  settled  and  with 
a  base  of  6  to  8  feet  will  be  found  satisfactory.  These  offer 
but  little  difficulty  in  cutting  and  harvesting  crops  while  high 
levees  are  often  troublesome  in  this  respect. 


METHODS  OF  PREPARING  LAND  93 

Rectangular  checks  are  often  preferred  to  the  contour  type. 
Fig.  46  shows  the  same  field  as  that  sketched  in  Fig.  45  prepared 
by  building  the  levees  in  straight  lines  thus  forming  a  series  of 
rectangles.  In  either  case  the  levees  are  generally  made  by 
scrapers  drawn  by  two  or  four  horses.  The  high  parts  within  the 
checks  are  removed  to  the  lower  spots  or  dumped  along  the  levees. 
The  proper  leveling  of  each  check  is  important.  The  size  of  the 
checks  depends  largely  upon  the  slope  of  the  land,  the  charac- 
ter" of  the  soil  and  the  head  of  water  available.  In  the  San 
Joaquin  Valley,  California,  where  the  check  method  is  used  more 
extensively  than  in  any  part  of  arid  America,  the  average  size  of 
the  checks  is  about  three-fourths  of  an  acre.  It  was  the  com- 
mon practice  when  irrigation  commenced  in  this  valley  to  make 
large  checks  containing  sometimes  as  much  as  25  acres  in  a 
single  check.  Later  practice  has  demonstrated  the  fallacy  of  this 
idea  and  large  checks  with  their  correspondingly  high  levees  con- 
taining over  5  acres  are  now  seldom  found  in  California. 

The  cost  of  checking  land  for  irrigation  including  ditches  and 
structures  ranges  from  $10  to  $30  per  acre  and  the  average  over 
a  large  part  of  the  San  Joaquin  and  Sacramento  Valleys  is  about 
$15  per  acre.  In  the  Tulare  Irrigation  District,  California, 
alfalfa  is  irrigated  by  the  check  method  with  a  head  of  water 
varying  from  5  to  10  cubic  feet  per  second  at  a  cost  of  about  50 
cents  per  acre.  The  cost  of  each  watering  on  large  areas  of  land 
under  the  Miller  and  Lux  canal  system  in  Fresno  and  Merced 
counties  where  contour  checks  are  used  is  from  75  to  90  cents  per 
acre.  An  irrigating  head  of  5  cubic  feet  per  second  will  cover  1 
acre  about  5  inches  deep  in  1  hour  and  at  this  rate  10  acres  per 
10-hour  day  can  be  irrigated.  Suitable  boxes  for  controlling 
the  water  passing  from  the  feed  ditch  into  each  check  greatly 
lessen  the  time  required  and  facilitate  the  ease  of  irrigation. 

22.  Basin  Method  of  Irrigation. — This  method  is  essentially 
the  check  method  adapted  to  the  needs  of  orchard  irrigation. 
Hidges  of  loose  earth  are  thrown  up  midway  between  the  rows 
of  trees  in  two  directions  at  right  angles  to  each  other.  These 
form  a  large  number  of  square  basins,  or  enclosures,  with  a  tree 
at  the  center  of  each.  The  ridges  are  made  either  by  throwing 
up  two  furrows  with  an  ordinary  walking  plow  or  with  a  special 
implement  known  as  a  ridger.  There  are  various  forms  of  ridgers 


94  USE  OF  WATER  IN  IRRIGATION 

used,  the  most  common  of  which  is  shown  in  Fig.  47.  It  consists 
of  two  running  boards  made  of  2-inch  plank,  14  to  18  inches  high 
and  from  6  to  8  feet  long.  The  runners  are  shod  with  steel  on 
the  bottom  and  part  way  up  the  inner  side  to  prevent  wear  and 
lessen  the  draft.  They  are  from  4  to  5  feet  apart  at  the  front 
end,  15  to  24  inches  apart  at  the  rear  end,  and  held  in  position  by 
cross  pieces  and  straps  of  steel.  Another  implement  popular 
in  California  for  making  ridges  is  the  rotary  disk  which  throws 
the  earth  toward  a  common  ridge  in  the  center  and  requires  only 
one  trip  across  the  orchard  for  each  ridge.  In  cross  checking 
or  ridging  the  orchard  an  opening  is  left  at  each  corner  of  each 
basin.  An  ordinary  scraper  or  a  rotary  scraper  is  usually  used 
to  fill  these  gaps  or  openings;  occasionally  they  are  filled  with  a 


FIG.  47. — Ridger  used  in  basin  irrigation. 

shovel.     The  ridges  are  made  from  4  to  9  inches  high  depending 
upon  the  depth  of  water  applied  in  one  irrigation. 

There  are  several  methods  of  flooding  basins  practised.  One 
of  the  most  common  and  perhaps  the  best  method  is  shown  in 
Fig.  48.  Double  ridges  are  made  between  alternate  rows  of 
trees,  forming  a  small  ditch  through  which  water  is  conveyed 
from  the  head  ditch  in  the  direction  of  the  greatest  slope.  The 
basins  are  flooded  in  pairs  beginning  with  the  lowest  tier. 
Another  method  of  flooding  basins  is  to  let  the  water  from  the 
feed  ditch  take  a  zigzag  course  through  the  basins  by  making 
openings  in  opposite  corners  of  each  compartment.  The  prin- 
cipal objection  to  this  method  is  that  the  basins  nearest  the  head 
ditch  receive  the  most  water.  To  prevent  water  coming  in  con- 
tact with  the  trunks  of  the  trees,  which  is  considered  detrimental 


METHODS  OF  PREPARING  LAND 


95 


by  some  orchardists,  ridges  may  be  formed  between  the  rows  of 
trees.  These  form  small  basins  around  each  tree,  the  water 
being  applied  to  the  outer  basin.  Ordinarily  the  orchard  can 
be  graded  leaving  a  small  mound  around  each  tree  high  enough 
so  as  never  to  be  submerged. 

After  each  irrigation  the  ridges  are  worked  down  to  the 
general  ground  level  and  the  orchard  is  thoroughly  cultivated 
and  harrowed.  The  average  cost  of  preparing  the  land  for 
basin  irrigation  in  the  Santa  Clara  Valley,  California,  where  this 
form  of  irrigation  has  reached  its  highest  development  is  about 
70  cents  per  acre  and  the  average  cost  of  applying  water  is  about 
§1.90  per  acre.  The  basin  method  was  formerly  used  extensively 
in  southern  California  for  the  irrigation  of  citrus  fruits  but  has 


I 


FIG.  48. — Basin  method  of  irrigation. 

been  practically  abandoned  in  favor  of  the  furrow  method.  It 
is,  however,  still  used  on  some  of  the  heavier  clay  soils  and  for 
the  irrigation  of  numerous  walnut  orchards. 

23.  Sub  irrigation. — Crops  are  said  to  be  subirrigated  when 
the  irrigation  water  is  supplied  from  beneath  the  surface  and  is 
drawn  to  the  roots  by  the  force  of  capillarity.  The  water  used 
in  subirrigation  may  be  supplied  in  two  general  ways.  First, 
through  some  form  of  artificial  conduit,  such  as  tile  or  cement 
pipe,  and  second,  by  raising  the  natural  water  table  high  enough 
so  that  the  plants  can  draw  upon  it  for  their  growth.  The  first 
may  be  termed  artificial  subirrigation  and  the  second  natural 
subirrigation.  In  either  case  at  least  three  conditions  must 


96  USE  OF  WATER  IN  IRRIGATION 

exist  in  order  to  make  subirrigation  practicable:  namely,  a 
porous  surface  soil  which  allows  rapid  movement  of  the  mois- 
ture laterally  or  upward;  an  impervious  substratum,  and  drainage 
facilities  to  prevent  the  complete  waterlogging  of  the  land. 
There  are  few  localities  where  these  three  conditions  exist  simul- 
taneously and  the  area  of  land  adapted  to  subirrigation  is  there- 
fore very  restricted. 

ARTIFICIAL  SUBIRRIGATION. — Artificial  subirrigation  has  always 
seemed  very  attractive  to  the  uninitiated  since  it  is  in  theory 
an  ideal  method  of  distributing  the  water  in  the  soil.  It  reduces 
to  a  minimum  the  usual  waste  due  to  evaporation  and  run-off, 
the  water  can  be  easily  controlled  and  the  cost  of  application  is 
small.  However,  unless  the  conditions  described  above  prevail 
the  installation  of  a  subirrigation  system  is  very  apt  to  result  in 
failure,  and  even  when  all  conditions  are  favorable,  the  high  cost 
of  installation  makes  this  method  of  irrigation  unadvisable  unless 
valuable  crops  can  be  grown. 

Perhaps  the  most  successful  subirrigation  is  practised  in  the 
vicinity  of  Sanford,  Florida.  The  following  description  of  the 
methods  employed  in  Florida  and  other  sections  has  been  ex- 
tracted from  a  report  by  Milo  B.  Williams,  Irrigation  Engineer, 
of  the  U.  S.  Department  of  Agriculture. 

The  lands  in  the  vicinity  of  Sanford,  Florida,  are  sandy  and 
slope  gently  toward  the  lake  with  an  exceptionally  uniform  sur- 
face. They  are  known  as  the  "Palmetto  Flatwoods."  The  soil 
is  sandy  and  is  underlaid  by  hardpan  which  is  a  decided  advan- 
tage from  the  standpoint  of  subirrigation  since  it  forms  a  bottom 
for  the  moisture  reservoir,  thus  holding  the  water  close  to  the 
plant  roots  and  assisting  greatly  its  lateral  spread.  Water  is 
turned  into  the  irrigation  systems  from  flowing  wells  and  allowed 
to  run  until  the  whole  soil  area  is  saturated  to  the  surface.  Then 
the  tile  drains  are  opened  and  the  excess  is  allowed  to  drain  off. 
This  is  done  at  times  of  setting  out  young  plants  rather  than 
during  the  growth  of  the  crop. 

As  the  larger  part  of  the  land  is  naturally  too  wet  for  culti- 
vation and  must  be  drained  as  well  as  irrigated,  the  system  of 
tiling  used  is  designed  to  answer  both  purposes.  The  tile  system 
consists  of  a  water-tight  main  pipe  feeding  a  series  of  open- 
jointed  parallel  laterals  placed  16  to  18  inches  deep.  The  mains 


PLATE  III 


>FiG.  A. — Main  line  and  stop- 
boxes  for  subirrigation  systems 


FIG.  B  — Lateral  line  and 
stop-box. 


FIG.  C. — Details  of  stop-boxes. 


(Facing  page  96.) 


METHODS  OF  PREPARING  LAND  97 

are  laid  parallel  to  the  surface  regardless  of  grades  and  are 
l.x-atrd  on  the  highest  side  or  on  the  ridges  throughout  the  field 
so  that  the  laterals  slope  away  from  the  mains  at  the  proper 
depth.  The  mains  are  4-inch  to  5-inch  vitrified  terra  cotta 
pipe  which  is  obtained  in  2  1/2-foot  lengths  with  bell  ends.  The 
joints  are  made  water-tight  with  cement.  A  stop-box  is  placed 
at  the  intersection  of  each  lateral  with  the  main.  Holes  are  cut 
in  the  side  of  the  pipe  and  a  short  length  of  2-inch  steel  pipe  is 
cemented  into  place  to  form  a  connection  between  the  main 
and  the  head  stop-box,,  the  lateral  leading  out  from  the  stop-box. 
This  metal  pipe  also  forms  a  neck  in  which  wooden  plugs  or  other 
devices  may  be  inserted  to  control  the  flow  of  water. 

The  laterals  are  built  of  3-inch  clay  drain  tile  which  are 
obtained  in  12-inch  lengths.  The  pipe  are  laid  with  open  joints 
by  placing  the  short  lengths  end  to  end.  A  shovelful  of  sawdust 
or  cinders  is  placed  over  each  joint  to  prevent  fine  sand  from  work- 
ing into  the  line  and  stopping  up  the  pipe.  The  grades  for  the 
lateral  trenches  vary  from  a  1/2-inch  to  a  3-inch  fall  per  100  feet 
and  the  laterals  are  spaced  18  to  24  feet  apart,  the  shorter  dis- 
tance being  preferable. 

Stop-boxes  (Plate  III,  Fig.  A)  are  placed  in  the  lateral  lines 
(Plate  III,  Fig.  B)  at  intervals  of  100  to  400  feet  for  the  purpose 
of  checking  the  water  in  the  laterals  and  thus  securing  a  small 
pressure  in  the  line  above  the  boxes.  A  weir  division  wall 
(Plate  III,  Fig.  C)  is  inserted  near  the  inlet  side  containing 
two  metal-lined  openings,  one  a  3-inch  hole  on  a  level  with  the  tiles 
entering  and  leaving  the  box  and  the  other  a  1-inch  hole  about 
6  inches  higher.  When  the  water  is  not  to  be  held  in  the  pipe  line 
above  a  box,  the  lower  hole  is  left  open  so  that  the  water  can  pass 
down  the  line  freely.  When  the  water  is  to  be  held  up, .the  lower 
hole  may  be  plugged,  raising  the  water  to  the  upper  hole,  or  both 
may  be  plugged,  causing  the  water  to  rise  until  it  flows  over 
the  top  of  the  weir  wall  into  the  next  section  of  the  lateral.  The 
cost  of  this  system  ranges  from  $100  to  $125  per  acre,  not 
including  the  water  supply  or  the  drainage  outlet  from  the  field. 

The  first  irrigation  usually  is  applied  when  the  first  winter 
crops  are  planted  in  the  fall.  Later  irrigations  occur  at  inter- 
vals of  10  days  to  2  weeks  thereafter  during  the  growing  period. 
The  length  of  time  required  to  saturate  the  Sanford  soils  varies 


98 


USE  OF  WATER  IN  IRRIGATION 


from  2  or  3  hours  to  24  hours  depending  on  the  amount  of 
water  in  the  soil  prior  to,  irrigation,  the  depth  to  hardpan  and 
the  texture  of  the  soil. 

Some  of  the  peat  lands  of  Florida  are  also  subirrigated. 
Owing  to  the  lower  first  cost  and  the  difficulty  in  keeping  the 
tile  in  alignment  in  the  spongy  peat,  many  of  the  farmers 
in  this  section  use  wood  conduits  in  place  of  tile  (Fig.  49). 
Open  ditches  are  used  for  the  main  supply  and  drainage  conduits. 
The  laterals  are  made  of  rough  pine  lumber.  Boards  1X6 
inches  are  spliced  together  with  cleats  and  laid  in  the  bottom 
of  the  lateral  trench  with  the  cleats  underneath.  Small  1/4- 
inch  blocks  are  then  nailed  along  the  top  edges  at  intervals 
of  2  1/2  feet.  Boards  1X4  inches  and  1X5  inches  are  nailed 
together  forming  a  V-shaped  trough  which  is  inverted  over  the 


Soflk     Inlet  or  Outlet  Pipe  Set  in  Concrete 


FIG.  49. — Wooden  conduits  for  combined  drainage  and  irrigation. 

boards  in  the  trench  and  the  water  enters  and  leaves  through 
the  triangular  cavity  thus  formed.  The  laterals  are  spaced 
15  feet  apart,  15  inches  deep  and  on  a  slight  grade  or  no  grade. 
Three-foot  lengths  of  1  1/4-inch  galvanized  steel  pipe  are  placed 
in  the  ends  of  each  lateral  through  which  the  water  is  turned 
into  or  discharged  from  the  lateral.  Wooden  plugs  are  used 
in  the  ends  of  the  pipe  for  diverting  the  water  from  the  open 
ditches  to  the  laterals.  With  lumber  at  $16  per  thousand 
feet  B.  M.,  this  construction  costs  $90  per  acre. 

Subirrigation  from  open  ditches  is  also  practised  in  Florida, 
this  method  being  adapted  to  very  level  land  and  for  shallow- 
rooted  crops.  It  is  necessary  to  drain  this  land  during  the 
summer  season  and  to  irrigate  it  during  the  winter.  The 


METHODS  OF  PREPARING  LAND  99 

drainage  is  done  through  surface  ditches  cut  3  to  5  feet  deep. 
The  fields  are  drained  into  the  border  ditches  by  surface  laterals 
which  are  also  used  as  irrigation  laterals. 

The  land  is  prepared  for  irrigation  and  drainage  by  throwing 
the  soil  into  ridges  12  to  13  inches  high  and  4  feet  apart.  Irri- 
gation laterals  are  placed  at  intervals  of  40  feet  running  in  the 
direction  of  the  rows.  Grades  are  very  flat  and  the  water 
is  held  in  the  ditches  by  earthen  dams  until  the  moisture  shows 
on  the  surface  over  the  entire  area  between  ditches. 

Various  modifications  of  the  Florida  system  of  pipe  subirriga- 
tion  are  found  in  scattered  localities  throughout  the  central  and 
middle  western  states,  chiefly  in  Kansas,  Colorado,  and  Texas. 


FIG.  50. — Cement  pipe  for  subirrigation,  showing  porous  nozzle. 

Porous  concrete  tile  for  subirrigation  has  not  proved  very 
satisfactory  owing  to  the  fact  that  the  coarse  structure  permits 
the  free  absorption  of  soluble  substances  from  the  soil,  many 
of  which  react  with  the  cement  and  cause  it  to  disintegrate. 
There  is  also  danger  that  the  sediment  carried  by  the  water 
will  clog  up  the  pores  in  the  pipe  and  lessen  its  porosity. 

Continuous  concrete  pipe  has  also  been  used  to  some  extent 
but  owing  to  the  fact  that  it  is  .difficult  to  make  it  strong  enough 
TO  withstand  stresses  due  to  expansion,  contraction,  and  earth 
pressure,  this  kind  of  pipe  is  not  likely  to  come  into  general  use. 
From  an  hydraulic  standpoint,  non-porous  pipe  with  protected 
and  adjustable  openings  woul^l  seem  to  be  a  logical  type  of 
construction. 


100  USE  OF  WATER  IN  IRRIGATION 

Several  devices  are  used  to  protect  the  pipe  openings  against 
the  entrance  of  roots  and  dirt.  In  one  of  these  devices  small 
concrete  nozzles,  each  having  an  opening  through  its  length  are 
inserted  in  the  top  side  of  the  pipe.  Each  nozzle  is  covered 
with  a  concave  concrete  cap  cemented  at  each  end  but  left 
uncemented  on  the  sides  so  that  the  water  can  seep  out.  The 
distribution  of  water  is  controlled  by  varying  the  size  of  the  nozzle 
openings  to  suit  the  different  hydraulic  pressures.  Another 
device  consists  of  a  circular  block  of  porous  concrete  having  a 
convex  top  and  a  concave  bottom  with  the  bottom  so  hollowed 
as  to  form  a  cavity  (Fig.  50) .  This  is  cemented  over  an  opening 
in  the  pipe.  The  top  of  the  block  is  waterproofed  with  neat 
cement  so  that  water  seeps  through  the  porous  concrete  and 
enters  the  soil  through  the  sides  of  the  block.  The  discharge  is 
regulated  by  increasing  or  decreasing  the  size  of  the  block. 

Before  a  subirrigation  system  is  installed,  preliminary  tests 
should  be  made  on  a  small  area  of  the  tract  to  be  irrigated. 
These  tests  should  determine  the  amount  of  water  required  by 
a  given  subirrigated  area,  the  depth  to  which  the  water  percolates 
beneath  the  laterals  and  the  distance  to  which  it  spreads  laterally. 
When  it  has  been  determined  how  far  apart  to  space  the  laterals 
the  cost  can  be  determined  quite  accurately. 

Subirrigation  of  lands  which  contain  any  considerable  quantities 
of  soluble  salts  involves  great  risks  since  the  continuous  rising 
of  moisture  from  below  may  cause  an  accumulation  of  salts 
on  the  surface  which  will  in  time  make  the  land  unproductive. 

NATURAL  SUBIRRIGATION. — Frequently  the  seepage  water  from 
porous,  earthen  ditches  and  the  waste  water  from  irrigated 
areas  pass  through  the  subsoil  of  lower  fields  sufficiently  near 
the  surface  to  subirrigate  them.  In  other  places  these  seepage 
waters  collect  at  the  lower  levels  and  raise  the  ground  water 
near  enough  to  the  surface  to  supply  the  plants  with  the  needed 
moisture. 

Perhaps  the  most  notable  subirrigated  area  in  the  arid  region 
is  found  in  the  vicinity  of  the  towns  of  St.  Anthony  and  Sugar 
City  in  the  upper  Snake  River  Valley,  Idaho.  This  subirrigated 
district  comprises  an  area  of  about  60,000  acres.  The  surface 
soils  in  this  area  are  gravelly  or  clay  loam,  varying  in  depth 
from  1  1/2  to  6  feet.  The  land  slopes  at  the  rate  of  about  10  feet 


METHODS  OF  PREPARING  LAND  101 


per  mile.  An  impervious  lava  rock-  is^fouiul- at  it  <lepihj Varying 
from  a  few  feet  to  90  feet.  This  hind  was  at  first  irrigated  by 
the  usual  methods  but  owing  to  the  porous  nature  of  the  soil 
the  water  rapidly  sunk  to  the  bed  rock  and  it  was  not  possible 
to  retain  sufficient  moisture  in  the  surface  soil  to  insure  good 
crops.  In  time,  however,  the  subsoil  filled  with  water  and  the 
top  soil  began  to  receive  moisture  from  below.  This  led  to  a 
new  method  of  irrigation.  The  water  is  supplied  to  the  fields  in 
shallow  ditches  3  feet  wide,  6  inches  deep  and  not  to  exceed  1320 
feet  long.  These  ditches  divide  the  farm  into  strips  100  to  300 
feet  wide.  By  this  method  no  water  is  spread  over  the  surface, 
the  laterals  merely  distributing  from  15  to  20  miner's  inches  to 
different  parts  of  the  field  where  it  soon  joins  the  ground  water 
by  sinking  through  the  bottoms  of  the  shallow  ditches.  The 
water  is  kept  running  continuously  until  the  water  table  rises 
high  enough  to  supply  the  needed  moisture  to  the  roots  of  the 
plants.  Thereafter  the  ground  water  is  regulated  by  the  amount 
of  water  turned  into  the  supply  ditches.  The  rise  and  fall 
of  the  ground  water  is  determined  by  means  of  small  boxes  set 
in  the  ground  3  to  5  feet  deep.  From  20  to  30  boxes  are  usually 
required  for  each  80-acre  farm. 

A  system  of  subirrigation  very  similar  to  that  just  described 
is  practised  in  parts  of  the  San  Luis  Valley,  Colorado.  The  best 
results  are  obtained  on  porous  sandy  loam  soils  underlaid  at  a 
depth  of  several  feet  by  an  impervious  stratum  and  on  land 
having  a  slope  of  5  to  10  feet  per  mile.  Most  of  the  land  in  the 
valley  is  of  uniform  slope  and  the  custom  is  to  run  the  ditches 
parallel  to  the  section  lines  in  the  direction  having  the  least 
slope.  They  are  spaced  at  intervals  varying  from  50  to  250  feet 
according  to  the  character  of  the  soil,  the  depth  to  the  normal 
water  table  and  the  amount  of  irrigation  in  the  neighborhood 
affecting  the  water  table. 

There  are  many  modifications  of  the  above  method  in  the 
San  Luis  Valley.  Where  the  soil  is  thin  or  leveling  is  impracti- 
cable for  any  reason,  the  field  ditches  are  carried  along  the  ridges. 
In  the  river  bottoms,  sloughs  or  old  channels  are  dammed  and 
kept  full  of  water  during  the  season.  In  other  cases  small  res- 
ervoirs have  been  built  to  catch  excess  water  which  is  allowed  to 
seep  out  and  saturate  the  subsoil. 


102  USlB  OF 'WATER  IN  IRRIGATION 

24.  Spray  Irrigation.-— In  spray  irrigation  water  is  applied  to 
the  surface  of  soils  and  crops  in  the  form  of  rain  or  mist.  This 
method  has  long  been  used  in  the  irrigation  of  lawns  in  western 
cities.  When  one  considers  the  high  rates  charged  by  companies 
and  municipalities  for  domestic  water  supplies  and  the  large  per- 
centage of  such  supplies  which  is  used  for  sprinkling  lawns  he  is 
surprised  at  the  crudeness  and  inefficiency  of  the  equipment  and 
methods  employed. 

In  recent  years  successful  attempts  have  been  made  not 
only  to  improve  the  practice  of  spray  irrigation  but  to  extend 
its  use  to  gardens  and  fields.  In  outlining  its  broader  scope 
in  the  irrigation  of  fields,  the  writer  has  been  guided  by  the 
recommendations  made  by  Milo  B.  Williams,  to  eastern  irri- 
gators  in  assisting  them  to  install  suitable  plants  for  the  irriga- 
tion of  small  areas  throughout  the  humid  region.  These  plants 
are  designed  to  supplement  a  scanty  or  unequal  and  always  un- 
certain rainfall  by  furnishing  relatively  small  quantities  of  water 
to  truck,  small  fruit  and  orchards  at  the  right  time.  The  large 
profits  derived  from  such  crops,  the  high  cost  of  artificial  fertili- 
zers, the  uneven  character  of  the  surface  of  fields,  the  growing 
of  two  or  more  crops  on  the  same  field  in  one  season  and  the  ad- 
vantages of  being  able  to  control  the  soil  moisture  in  cultivating 
and  recropping,  fully  justify,  under  favorable  conditions,  the 
heavy  expense. 

The  essential  features  of  every  system  designed  for  spray 
irrigation  are  (1)  nozzles,  (2)  feed  pipes  and  (3)  a  pumping  plant 
or  its  equivalent.  The  design  of  nozzle  and  its  arrangement 
in  the  field  separate  the  types  of  spray  irrigation  into  three  more 
or  less  distinct  groups  which  are  herein  briefly  described  under  the 
following  heads. 

POETABLE  NOZZLE  TYPE  . — This  consists  of  sets  of  nozzles  and 
hose  which  can  be  moved  from  place  to  place  and  attached  to 
hydrants  conveniently  located  throughout  the  field.  The 
hydrants  are  generally  spaced  100  to  200  feet  apart  and  each  con- 
trols an  area  of  proportionate  size.  The  hydrants  are  usually 
made  of  a  short  length  of  pipe  projecting  2  or  3  feet  above  the 
surface  and  capped  with  spigot  or  hose  connection.  In  some 
cases  special  hydrants  are  used.  The  portable  nozzles  are  at- 
tached to  lengths  of  hose  which  reach  at  least  one-half  the  dis- 


METHODS  OF  PREPARING  LAND  103 

tance  between  the  hydrants.  For  garden  or  lawn  irrigation  a 
3/4-inch  hydrant  and  hose  can  be  used.  Grass  sods,  such  as  put- 
ting greens,  public  parks,  and  meadows  are  often  irrigated  with 
larger  hose  ranging  up  to  2  1/2  inches  in  diameter. 

Some  gardeners  prefer  to  dispense  with  the  nozzle  in  spraying 
greenhouse  plants  and  seed-beds,  and  merely  pinch  the  end  of 
the  hose  between  the  fingers  in  such  a  way  as  to  produce  the 
desired  spray.  There  are  a  number  of  adjustable  nozzles  on 
the  market  which  can  be  made  to  discharge  a  solid  stream  or  any 
degree  of  fineness  of  spray.  One  type  requires  to  be  held  con- 
stantly in  the  hand  or  moved  very  frequently.  Another  type 
which  sprays  a  circular  area  can  be  set  in  one  place  and  allowed 
to  run  for  some  time  before  moving  is  necessary.  The  last  type 
is  generally  supported  on  a  stool  or  sharp-pointed  rod  which  can 
be  stuck  into  the  ground  and  the  nozzle  held  3  or  4  feet  above  the 
surface. 

Where  a  large  quantity  of  water  is  to  be  applied  through  a  large 
hose,  a  rotating  nozzle  mounted  on  a  small  truck  meets  the  re- 
quirements. These,  nozzles  discharge  from  60  to  100  gallons  per 
minute  under  a  30-pound  presspre  and  cover  a  circular  area  75  to 
100  feet  in  diameter. 

STATIONARY  NOZZLE  TYPE. — The  stationary  type  of  spray  irri- 
gation consists  of  a  system  of  equally  spaced  nozzles  over  the 
field  so  that  any  portion  can  be  sprayed  by  turning  on  the  water. 
The  feeder  system  forms  a  network  of  piping  so  constructed  that 
the  nozzles  are  about  30  feet  from  each  other  and  set  on  the 
"  diamond."  This  makes  the  circular  areas  covered  by  the  noz- 
zles fit  together  with  the  least  overlapping  and  yet  cover  the 
bulk  of  the  ground.  The  nozzles  are  placed  on  3/4-inch  risers  5 
to  6  feet  above  the  surface.  The  nozzles  commonly  used  may  be 
divided  into  three  groups,  viz.,  (1)  solid  nozzles  with  no  moving 
parts,  (2)  adjustable  nozzles  with  parts  which  can  be  manipu- 
lated to  change  their  capacities  or  degree  of  spray  and  (3)  rotary 
nozzles  with  moving  parts  which  assist  in  the  distribution  of  the 
water  by  centrifugal  forces. 

The  capacities  of  some  of  the  popular  nozzles  were  found  by 
actual  test  to  be  from  3.2  gallons  per  minute  to  14.5  gallons  per 
minute  when  operating  under  20  pounds  pressure  per  square  inch, 
and  from  3.5  to  18.4  gallons  under  25  pounds  pressure.  The 


104  USE  OF  WATER  IN  IRRIGATION 

circular  areas  covered  by  the  different  nozzles  varied  from  30  to 
40  feet  in  diameter.  The  distribution  of  water  over  the  areas 
was  somewhat  uneven.  Most  nozzles  discharge  a  relatively 
large  percentage  of  the  water  in  an  annular  ring  from  10  to  30 
feet  in  diameter,  with  gradual  reductions  inside  and  outside  of 
this  ring. 

The  solid  nozzles  with  no  moving  parts  are  the  most  durable. 
Their  capacities  and  form  of  spray  can  not  be  varied  as  in  the  case 
of  the  adjustable  nozzle.  The  solid  nozzles  which  will  give  a 
wide  lateral  throw  are  of  large  capacities  and  demand  large  feeders. 

Rotary  nozzles  throw  the  greatest  distance  in  proportion  to 
their  capacities  but  in  larger  drops.  A  certain  amount  of  wear 
takes  place  which  in  time  reduces  their  efficiencies. 

Adjustable  nozzles  are  favored  by  some  truck  gardeners  be- 
cause of  the  fine  spray  which  can  be  obtained  when  desired.  The 
throw  is  usually  less  than  either  the  stationary  or  rotary  nozzle. 

OVERHEAD  NOZZLE  LINES. — The  system  commonly  known  as 
overhead  spray  irrigation  consists  of  a  series  of  nozzles  inserted 
in  parallel  pipe  lines  supported  above  the  surface  on  posts  in  such 
a  way  that  each  line  is  fed  from  a  main  at  one  end  and  irrigates 
a  strip  from  50  to  56  feet  in  width  the  length  of  the  field  (see 
Plate  IV). 

A  nozzle  line  is  made  of  galvanized  wrought  iron  or  steel  pipe 
into  the  shell  of  which  is  screwed  at  regular  intervals  small  brass 
nozzles.  The  pipe  is  supported  in  bearings  which  will  permit 
it  to  be  revolved,  thus  throwing  the  nozzles  from  side  to  side. 
The  nozzles  are  accurately  set  in  a  straight  line  so  that  all  will 
discharge  in  the  same  direction  and  irrigate  a  strip  parallel  to  the 
pipe  when  the  line  is  set  in  any  one  position.  Consecutive  strips 
can  be  irrigated  by  revolving  the  pipe  through  an  arc  at  different 
stages  until  the  entire  area  on  both  sides  is  covered.  Each  nozzle 
throws  a  clear  cut  solid  stream  which  becomes  broken  into  small 
drops  before  reaching  the  ground.  A  nozzle  line  is  connected 
to  the  feed  pipe  by  means  of  a  riser,  elbow,  patented  turning 
union,  and  nipples.  A  quick-opening  lever  gate  valve  is  placed 
in  the  riser  at  a  convenient  height.  The  lines  are  operated  from 
the  feeder  end  by  a  hand  or  power  turning  device. 

The  nozzle  lines  should  run  in  the  direction  of  cultivation  so 
that  the  crop  rows  will  parallel  the  pipe  supports.  The  feeder 


PLATE  IV 


PLATE  IV 


FIG.  B. — Enlarged  view  of  overhead  nozzle  line. 


METHODS  OF  PREPARING  LAND 


105 


pipe  should  run  under  ground  at  right  angles  to  the  nozzle  lines 
and  he  so  located  as  to  use  the  least  amount  of  large  pipe. 

The  size  of  pipe  to  use  in  a  nozzle  line  is  determined  by  the 
number  and  capacities  of  the  nozzles  it  contains.  The  end  con- 
necting to  the  feeder  is  the  larger  to  carry  all  the  water  but  as  the 
water  is  diminished  by  the  nozzles  the  pipe  can  be  made  smaller 
in  proportion  to  the  amount  withdrawn. 

The  following  table  illustrates  the  sizes  of  pipe  used  in  nozzle 
lines  of  different  lengths  for  a  nozzle  having  a  capacity  of  1/5 
gallon  per  minute  and  a  spacing  of  4  feet. 

TABLE  No.  17 


Total 
length, 
feet 

Proportioned  sizes  and  lengths  of  pipe 

3/4  Inch 

1  Inch 

1  1/4  Inch 

11/2  Inch 

2  Inch 

100 
150 
200 
300 
400 
500 
600 
700 
800 

100 
90 
90 
90 
90 
90 
90 
90 
90 

60 
110 
150 
150 
150 
150 
150 
150 

160 

150 
150 
150 
150 

110 
150 
150 
150 

60 
160 

260 

Xozzle  lines  are  usually  spaced  50  to  56  feet  apart  and  operated 
under  30  pounds  pressure.  When  it  is  desired  to  irrigate  more 
rapidly  larger  pipe  lines  and  nozzles  must  be  used  or  the  small 
nozzles  may  be  spaced  closer  together  on  a  larger  pipe.  It  seldom 
pays  to  use  2-inch  pipe  in  nozzle  lines  but  is  cheaper  and  better 
to  run  more  feeders. 

There  are  two  popular  methods  of  supporting  nozzle  lines,  i.e., 
directly  on  posts  or  suspended  from  a  high  cable.  A  post  which 
will  hold  the  pipe  just  above  the  crop  or  one  that  elevates  the  line 
r»  1  2  feet  above  the  surface  so  a  horse  can  pass  under  are  the  com- 
mon designs.  The  higher  design  permits  cross  cultivation  and  is 
popular  among  truck  farmers  and  berry  growers,  while  the  low 
place  the  system  less  in  sight  for  flower  beds,  lawns  and 
small  home  gardens.  The  posts  should  be  of  concrete,  pipe,  or 
wood  treated  with  asphaltum,  tar,  or  paint.  They  should  be 
5  to  6  inches  at  the  base  if  of  wood,  and  set  in  the  ground  21/2 
to  3  feet  and  of  ample  length  to  be  cut  off  at  the  right  height 


106  USE  OF  WATER  IN  IRRIGATION 

after  set  to  give  the  nozzle  lines  uniform  appearance.  Nozzle 
lines  should  be  supported  every  18  feet. 

Suspending  the  nozzle  lines  from  a  high  cable  supported  on 
large  posts  is  a  construction  used  by  some  farmers  because  of  the 
less  obstruction  to  cultivation.  The  posts  are  spaced  from 
75  to  100  feet  apart  and  may  be  either  of  wood  or  4-inch  steel 
pipe.  They  should  be  from  two  to  three  times  as  high  as  the 
pipe  is  to  be  held.  The  cable  is  held  on  the  tops  of  the  posts  by 
heavy  hooks  but  free  to  draw  lengthwise.  Heavy  spreading 
anchors  must  hold  the  ends  of  the  cable  which  are  generally 
fastened  to  buried  logs  or  concrete.  A  turn  buckle  should  be 
inserted  near  the  end  of  the  cable  for  use  in  taking  up  the  slack 
at  different  times.  The  proper  weight  of  cable  to  use  depends 
upon  the  spacing  and  height  of  the  posts  and  the  weight  of  pipe 
to  be  supported.  These  facts  should  be  furnished  to  the  cable 
dealer  and  a  sufficient  weight  used. 

The  nozzle  line  is  suspended  from  the  cable  by  varying  lengths 
of  galvanized  wire  spaced  15  feet  apart  and  fastened  to  hooks  in 
which  the  pipe  lies.  The  nozzle  lines  can  be  graded  uniformly 
by  adjusting  the  lengths  of  the  wire  hangers.  Cable  suspension 
generally  costs  15  to  20  per  cent,  more  than  direct  post  support. 

FEEDER  SYSTEM. — The  designing  of  a  feeder  system  should 
be  governed  by  the  type  of  nozzles  used,  their  individual  capacities, 
and  the  amount  of  water  to  be  carried  through  each  line.  The 
field  should  be  divided  into  irrigation  units.  The  size  of  units 
will  be  limited  either  by  the  available  water  supply  or  by  the  rate 
of  irrigation  desired  for  the  entire  field.  The  main  feeder  should 
be  located  to  make  it  as  short  as  possible  and  at  the  same  time 
intersect  the  branch  feeders  at  the  most  efficient  points.  The 
capacity  of  the  main  should  be  equal  to  that  of  the  pump  and 
that  needed  for  one  irrigation  unit.  The  main  can  be  reduced  in 
size  as  the  water  is  diminished  by  branches  in  the  most  remote  unit. 

The  branch  feeders  should  be  of  capacities  to  supply  their 
respective  nozzles  and  reduced  in  size  in  correspondence  to  the 
amount  of  water  to  be  carried  at  different  points.  No  pipe  should 
be  small  enough  to  generate  excessive  frictional  resistance. 

The  following  table  gives  the  size  of  metal  pipe  to  use  for  differ- 
ent quantities  of  water  in  order  to  keep  the  frictional  resistance 
within  moderate  limits,  for  straight  pipe  lines  under  500  feet  in 


METHODS  OF  PREPARING  LAND 


10: 


length.     For  longer  lines  it  is  generally  advisable  to  increase  the 
to  the  next  larger.     Allowance  should  also  be  made  for  any 

sharp  bends. 


TABLE  No.  18 


Gallons  per  minute        Size  of  pipe,  inches  [    Gallons  per  minute     j    Size  of  pipe,  inches 


5 

1 

350 

5 

10 

11/4 

400 

6 

20 

11/2 

500 

6 

30 

2 

600 

7 

50 

2 

700 

7 

75 

21/2 

800 

8 

100 

3 

900 

8 

150 

31/2 

1000 

9 

200 

4 

250 

4 

300 

5 

The  pipe  used  for  feeder  systems  consists  of  common  steel  or 
wrought-iron  water  pipe  with  threaded  joints,  or  cast-iron  pipe 
with  leaded  joints,  or  riveted  steel  pipe  with  flange  or  bolted 
joints.  Reinforced  concrete  pipe  can  also  be  used  for  this  pur- 
pose if  it  is  properly  made  and  the  pressure  is  carefully  regulated. 

Steel  pipe  should  be  galvanized  and  the  exposed  threads  on 
both  steel  and  wrought  iron  should  be  painted.  Black  guaran- 
teed wrought-iron  pipe  is  more  durable  than  steel  and  often  used 
in  preference  to  galvanized  steel.  The  rust  which  forms  on 
black  pipe  may  give  some  trouble  in  filling  nozzles.  It  is 
customary  to  use  steel  or  wrought  pipe  in  sizes  up  to  5  or  6  inches. 
(  ast-iron  pipe  becomes  cheaper  for  larger  sizes  unless  it  must  be 
shipped  long  distances.  Cast  iron  is  the  most  durable  of  these 
metal  pipes  and  may  be  used  in  the  lightest  weights  made. 
Riveted  steel  pipe  is  light  in  weight  and  comes  in  long  lengths 
making  it  the  cheapest  to  lay.  This  pipe  if  well  galvanized  after 
making  is  good  to  use  when  long  shipments  and  large  pipe  are 
necessary. 

All  feeder  systems  should  be  put  underground  below  the  depth 
of  cultivation  where  possible,  and  ample  provision  should  be  made 
for  draining  in  winter  and  for  flushing  out  once  or  twice  per  year 
to  blow  out  rust  scales,  sediment,  etc.  This  is  best  accomplished 
by  having  removable  plugs  at  the  end  of  each  main  and  feeder 
and  at  all  low  points  in  all  lines. 


108  USE  OF  WATER  IN  IRRIGATION 

PUMPING  PLANTS. — The  five  factors  to  be  considered  in  design- 
ing a  pumping  plant  for  spray  irrigation  are  the  amount  of  water 
to  be  pumped  per  minute;  the  static  head,  or  vertical  distance 
between  the  level  of  the  water  supply  and  the  highest  nozzle; 
the  friction  and  velocity  heads  or  the  total  resistance  to  the  water 
passing  through  the  pipe  lines;  and  the  pressure  head,  or  the 
amount  of  pressure  necessary  to  operate  the  nozzles. 

The  capacity  of  the  plant  should  be  the  same  as  that  of  the 
feeder  system  (see  page  106).  The  static  head  should  be  deter- 
mined by  a  survey  in  the  field  with  an  engineer's  level  and  due 
allowance  made  for  the  distances  the  water  level  may  be  lowered 
when  pumping  as  well  as  the  height  of  the  nozzles  above  the 
ground.  The  frictional  and  velocity  heads  can  be  obtained  from 
hydraulic  tables  when  the  kind,  size,  and  length  of  pipe  and  the 
amounts  of  water  are  known.  The  pressure  head  is  determined 
by  the  type  of  nozzle  used. 

Knowing  the  capacity  and  the  sum  of  the  heads,  the  amount  of 
work  which  the  plant  must  perform  is  determined  and  the  horse- 
power can  be  calculated  to  correspond  to  the  guaranteed  efficiency 
of  the  pump  to  be  used. 

The  most  desirable  type  of  pump  to  use  in  any  one  case  must 
be  determined  by  the  above  factors  and  any  restricting  conditions 
of  the  water  supply,  such  as  a  deep  well,  water  containing  sedi- 
ment, etc.  All  factors  and  conditions  should  be  furnished  to 
several  manufacturers  so  that  they  can  bid  on  their  most  adapt- 
able machinery  and  the  farmer  obtain  the  most  efficient  equip- 
ment for  the  expenditure. 

Power  displacement  pumps  of  the  piston  and  plunger  types,  and 
high  pressure  centrifugal  pumps  are  the  designs  commonly  used 
for  spray  irrigation  plants. 

The  single  cylinder  displacement  pumps  are  adaptable  to  small 
plants  up  to  75  gallons  per  minute,  where  the  water  is  within 
25  feet  of  the  pump.  This  type  is  sometimes  the  only  one  ad- 
visable to  use  in  deep  wells  for  any  quantity  of  water.  The  piston 
should  be  double  acting  and  lift  water  when  moving  in  either  direc- 
tion. The  pump  should  be  equipped  with  a  large  air  chamber 
which  will  act  as  a  cushion  and  reduce  the  pulsations  of  the  water 
in  the  pipe  lines  to  a  minimum.  The  power  head  and  cylinder 
are  built  in  a  compact  unit  for  low  suction  lifts  but  must  be  sepa- 


METHODS  OF  PREPARING  LAND  109 

rated  for  deep  well  use.  In  the  latter  case  it  is  best  to  have  the 
cylinder  always  under  water  if  possible. 

The  duplex  and  triplex  displacement  pumps  are  adaptable 
for  pumping  any  quantity  of  water  where  the  suction  lift  is  within 
25  feet.  These  pumps  are  built  in  both  single-  and  double-acting 
types.  Light  weight  double-acting  duplex  and  single-acting  tri- 
plex are  commonly  used.  Smaller  air  chambers  in  comparison 
to  the  amount  of  water  can  be  used  than  on  simplex  pumps  as 
the  multicylinders  give  a  more  steady  discharge.  These  pumps 
are  considered  the  most  efficient  types  when  kept  in  repair  and 
direct-connected  to  the  prime  mover.  The  connection  to  the 
engine  should  be  made  by  a  friction  clutch  which  can  be  thrown 
in  or  out  at  will  when  the  engine  is  running.  A  belt  connection 
can  be  used  where  desirable  but  takes  more  floor  space  and  more 
power  is  lost  in  transmission.  A  direct-connected  unit  is  the 
most  efficient  and  compact  construction.  The  reduced  power 
necessary  to  run  an  efficient  high-priced  pump  may  make  it 
cheaper  to  install  and  operate  than  a  belt-connected  inexpensive 
pump  which  demands  a  larger  engine  and  house. 

Centrifugal  pumps  can  be  used  to  advantage  for  spray  irriga- 
tion under  some  conditions.  Large  centrifugal  pumps  are  more 
efficient  than  small  ones.  Centrifugal  pumps  also  decrease  in 
efficiency  as  the  head  against  which  they  must  work  increases. 
Therefore,  the  larger  the  plant  and  the  lower  the  lift  the  more 
adaptable  is  a  centrifugal  pump.  Where  the  total  head  does  not 
exceed  100  feet  a  single-stage  high-pressure  pump  may  be  used. 
These  pumps  should  be  built  for  high  speed  with  long  bearings 
and  adequate  oiling  facilities.  Two-stage  centrifugal  pumps 
should  be  used  for  heads  between  100  and  ^50  feet  as  they  can  be 
run  at  lower  speeds  than  the  single  stage  for  like  heads. 

The  efficiency  of  a  centrifugal  pump  may  not  be  as  high  in  the 
beginning  as  a  good  displacement  pump  but  unless  the  displace- 
ment pump  is  kept  in  the  best  of  repair  its  efficiency  is  apt  to 
drop  below  that  of  the  centrifugal  which  maintains  its  efficiency 
longer  under  wear.  The  centrifugal  is  the  simplest  of  pumps 
and  the  repair  bills  are  correspondingly  small.  It  is  seldom  that 
a  centrifugal  can  be  direct  connected  to  the  prime  mover  unless 
the  power  is  electricity  in  which  case  the  centrifugal  should  always 
be  considered. 


CHAPTER  V 
WASTE,  MEASUREMENT,  DELIVERY  AND  DUTY  OF  WATER 

25.  The  Low  Efficiency  of  Irrigation  Water.— The  area  of  land 
irrigated  in  the  United  States  at  the  present  time  (1914)  is  about 
15,500,000  acres.  Probably  not  less  than  75,000,000  acre-feet 
of  water  are  diverted  annually  from  streams,  reservoirs,  wells  and 
other  sources  of  supply  to  water  this  area.  Some  idea  of  the  mag- 
nitude of  the  amount  of  water  supplied  for  irrigation  may  be  formed 
by  stating  that  if  spread  evenly  over  a  territory  the  size  of  the 
State  of  New  York  it  would  cover  it  to  a  depth  of  over  28  inches. 
To  convey  so  much  water  often  from  distant  sources  and  distribute 
it  over  cultivated  land  render  necessary  a  large  number  of  canals 
and  ditches.  These  channels  are  for  the  most  part  excavated 
in  earth  and  except  in  a  few  cases  a  large  percentage  of  the  water 
which  flows  through  them  is  lost  by  absorption  and  percolation 
along  the  route.  Coupled  with  the  transmission  losses  are  to  be 
found  other  losses  arising  from  improper  methods  of  use  and  lack 
of  skill  in  applying  water.  An  estimate  of  all  losses  based  on 
water  measurements  and  experiments  shows  that  for  every  3 
gallons  of  water  diverted  from  natural  streams,  only  about  1  gal- 
lon subserves  a  useful  purpose  in  nourishing  plant  life.  In  other 
words,  the  general  average  efficiency  of  irrigation  water  is  less 
than  35  per  cent.  The  waste  which  lowers  the  efficiency  to  one- 
third  the  maximum  is  all  the  more  to  be  deplored  by  reason  of 
the  fact  that  irrigation  water  so  valuable  to  the  West  is  rapidly 
becoming  scarce  while  fertile  raw  land  without  a  water  right  is 
plentiful  and  cheap.  Based  on  the  acreage  which  a  unit  of  water 
now  serves,  it  is  doubtful  if  more  than  50,000,000  acres  can  ever 
be  irrigated.  The  Census  returns  for  1910  show  that  in  the  17 
states  comprising  the  arid  region,  173,000,000  acres  were  classed 
as  improved  farm  lands.  Just  how  much  more  land  can  be 
improved  of  the  total  extent  of  arable  land  in  the  West  is  not 
known.  This  much,  however,  is  certain,  that  when  every  gallon 

110 


WASTE,  MEASUREMENT,  AND  DELIVERY      111 

of  the  available  water  supply  is  economically  used,  vast  areas 
of  rich  farming  lands  will  be  unreclaimed  for  lack  of  water. 

26.  Waste  of  Water  Due  to  Seepage  and  Other  Causes.— The 
largest  loss  of  irrigation  water  is  due  to  the  well-nigh  universal 
practice  of  conducting  it  in  earthen  ditches.  In  1910  the  census 
enumerators  reported  81,837  main  and  lateral  ditches  aggregating 
125,591  miles  in  length.  At  that  time  probably  less  than  4 
per  cent,  of  the  total  number  was  lined  or  otherwise  made  im- 
pervious, thus  leaving  fully  120,000  miles  of  earthen  channels. 
The  loss  of  water  in  such  channels  may  be  grouped  under  leaks, 
evaporation  and  seepage.  The  first  is  due  to  poor  workmanship 
or  carelessness  in  operation  or  both  and  can  be  readily  remedied. 
The  second  is  small  in  comparison  to  the  volume  carried  and  on 
an  average  represents  less  than  one-fourth  of  1  per  cent,  of  the 
flow,  while  the  third  is  the  main  source  of  waste. 

SEEPAGE  LOSSES. — Opinions  differ  as  to  the  relative  merits  of 
the  two  methods  of  expressing  seepage  losses  in  canals.  One 
method  expresses  the  loss  per  mile  in  the  percentage  of  flow  of  the 
canal  while  the  other  expresses  the  loss  in  24  hours  in  terms  of 
cubic  feet  per  square  foot  of  wetted  area.  Both  of  these  methods 
have  their  merits.  The  former  gives  one  a  ready  grasp  of  the 
efficiency  of  a  canal  in  a  general  way  while  the  latter  permits  a 
more  detailed  estimate  of  the  loss  which  may  be  expected  from 
a  given  section  of  a  canal  when  the  conditions  existing  in  it  have 
been  carefully  studied.  However,  seepage  losses  from  canals 
are  governed  by  many  variable  and  interdependent  conditions, 
the  combined  influence  of  which  makes  it  very  difficult,  if  not 
altogether  impracticable,  to  reduce  to  a  mathematical  formula. 
The  writer  is  convinced  that  no  refinement  of  calculation  for 
estimating  seepage  losses  in  proposed  canals  is  warranted  at  this 
time  without  considerable  data  directly  applicable  to  individual 
conditions  and  even  when  this  is  obtainable  the  accuracy  of  the 
estimate  will  depend  largely  upon  the  skill  as  well  as  upon  the 
experience  and  judgment  of  the  estimator. 

It  is  not  within  the  scope  of  this  publication  to  include  a  de- 
tailed discussion  of  the  various  factors  influencing  seepage,  but 
in  order  to  form  a  reliable  estimate  of  the  loss  by  seepage  from  a 
proposed  canal,  the  principal  factors  should  be  carefully  consid- 
ered. Briefly  these  are: 


112 


USE  OF  WATER  IN  IRRIGATION 


1.  Size  and  shape  of  grains  and  general  character  of  materials. 

2.  Capillarity  and  gravitation.  % 

3.  The  gradual  deposition  of  silt. 

4.  Depth  of  water  over  the  wetted  perimeter. 

5.  The  relation  which  the  wetted  perimeter  of  the  canal  bears  to  the 
other  hydraulic  elements. 

6.  Velocity  of  water  in  canal. 

7.  Inflow  of  seepage  water. 

8.  Temperature  of  the  soil  and  the  water. 

Table  No.  19  shows  the  close  relation  existing  between  the 
unit  loss  as  expressed  in  percentage  of  flow  and  the  size  of  a  canal. 
It  has  been  compiled  from  data  obtained  from  various  sources 
which  have  been  published  in  Bull.  126,  U.  S.  Department  of 
Agriculture,  by  the  author.  It  is  interesting  to  note  the  fairly 
constant  decrease  in  the  average  loss  in  per  cent,  per  mile  as  the 
capacity  increases. 

TABLE  No.  19 


Capacity  of  canal,  second-feet 

Number  of  tests 

Average    loss    per  mile, 
per  cent. 

Less  than  1   

16 

25  7 

1  to  5 

37 

20  2 

5  to  10  

30 

11.7 

10  to  25  
25  to  50 

49 

48 

12.1 
5  5 

50  to  75  

31 

4.3 

75  to  100  

26 

2.7 

100  to  200  
200  to  800  
800  and  over  

45 
27 
14 

1.8 
1.2 
1.0 

PEEVENTION  OF  SEEPAGE  LOSSES. — Seepage  losses  in  porous 
channels  may  be  greatly  lessened  by  a  lining  of  impervious  mate- 
rial, such  as  clay  or  fine  silt.  Sometimes  the  beds  of  such  chan- 
nels contain  more  or  less  fine  material  mixed  with  the  coarse  and 
puddling  may  then  be  used  to  advantage.  Puddling  can  best 
be  done  by  making  use  of  the  canal  after  being  moistened  as  a 
temporary  feeding  ground  for  sheep  or  goats.  Whenever  the 
material  is  too  coarse  to  puddle,  good  puddling  material  may  be 
hauled  and  spread  over  the  surface  of  the  canal.  It  is  then  mois- 
tened and  tamped  or  puddled  by  the  feet  .of  domestic  animals. 
After  securing  a  clay  lining  in  this  manner  it  is  well  to  ram  coarse 
gravel  into  the  surface,  thereby  making  a  clay  concrete. 

In  all  irrigation  channels  except  those  subject  to  erosion,  a 


WASTE,  MEASUREMENT,  AND  DELIVERY      113 

gradual  sedimentation  takes  place  which  renders  them  more 
impervious  with  age.  Whenever  water  of  silt-laden  streams  is 
run  through  canals  the  bottom  soon  becomes  quite  impervious 
necessitating  frequent  removal  by  cleaning.  In  fact  the  dis- 
charge of  all  streams  subject  to  floods  carries  during  periods  of 
high  water  more  or  less  silt,  a  part  of  which  is  deposited  in  the 
artificial  channels  and  tends  to  make  them  water-tight. 

A  coating  of  heavy  petroleum  oil  containing  a  large  percentage 
of  asphaltum  was  applied  to  a  few  canals  in  California  at  the  rate 
of  2  to  3  gallons  per  square  yard  but  the  results  of  the  experiments 
have  not  justified  the  extensive  use  of  petroleum  for  this  purpose. 

At  a  time  when  lumber  was  cheap  and  Portland  cement  ex- 
pensive it  was  common  practice  to  line  the  weak  and  leaky  beds 
of  canals  with  lumber  in  the  form  of  flumes.  The  short  life  of 
wood,  particularly  when  in  contact  with  earth,  the  high  cost  of 
maintenance,  the  rapid  increase  in  the  price  of  lumber  and  the 
corresponding  decrease  in  the  price  of  cement  have  all  tended  to 
lessen  the  use  'of  wooden  linings. 

Concrete  lining  is  now  regarded  as  the  best  and  as  a  rule  the 
most  economical  lining  to  use  in  the  prevention  of  seepage  losses 
in  irrigation  ditches  and  canals.  A  large  amount  of  concrete 
lining  has  been  laid  during  the  past  5  years  and  plans  are  under 
way  for  still  larger  investments  in  the  future  for  this  class  of 
construction.  The  cost  of  concrete  lining  varies  with  the  thick- 
ness, cost  of  materials,  transportation  charges  and  other  factors. 
Generally  the  highest  cost  does  not  exceed  15  cents  per  square 
foot  of  surface  lined,  the  lowest  5  cents  and  the  mean  10  cents 
per  square  foot.  The  methods  followed  in  lining  farm  ditches 
are  given  elsewhere. 

A  FLAT  RATE  PER  ACRE  CAUSES  WASTE. — In  the  most  common 
form  of  water  right  contract  between  the  owners  of  a  canal  sys- 
tem and  the  water  users,  the  former  agree  to  deliver  a  fixed  quan- 
tity of  water  for  a  definite  area  of  land.  This  ratio  between  a 
unit  of  water  and  a  certain  number  of  acres  of  land  is  known  as  the 
duty  of  water  and  is  usually  determined  while  the  land  is  in  its 
raw  state  and  before  the  real  needs  of  soil  and  crops  as  regards 
water  have  been  ascertained.  As  a  result  of  a  random  guess  at 
the  average  duty  over  large  tracts,  some  water  users  receive  under 
their  contracts  more  water  than  they  can  use  economically,  while 

8 


114  USE  OF  WATER  IN  IRRIGATION 

others  may  receive  too  little.  The  farmers  have  no  incentive  to 
economize  in  the  use  of  water  since  their  payments  are  based  on  a 
flat  rate  per  acre.  More  than  this,  the  combined  efforts  of  the 
latter  class  are  usually  exerted  in  inducing  the  company  to  in- 
crease the  general  average  duty. 

Wherever  it  is  practicable,  irrigation  water  should  be  measured 
out  to  users  in  the  same  way  that  water  for  domestic  purposes  is 
metered  out  to  consumers  and  let  each  pay  for  what  he  gets. 
Experiments  have  repeatedly  shown  that  where  water  is  delivered 
under  a  quantity  rate,  much  less  is  used  at  no  sacrifice  to  the 
yields  of  crops. 

If  the  quantity  rate  per  acre  can  not  be  adopted,  it  is  usually 
feasible  to  form  such  a  combination  of  the  two  methods  as  will 
serve  the  same  purpose.  In  this  combined  method  a  minimum 
quantity  of  water  per  acre  must  be  paid  for  by  all  users  but  to  those 
who  use  more  an  additional  charge  is  made  for  all  excess.  This 
method  has  been  in  vogue  for  years  in  the  Imperial  Valley,  Cali- 
fornia, and  has  resulted  in  saving  annually  enormous  quantities 
of  water.  Each  water  user  is  obliged  to  pay  50  cents  for  1  acre- 
foot  of  water  for  each  share  of  stock  which  he  owns  whether  he 
uses  the  water  or  not.  If  he  desires  more  water  during  any  1 
year  he  has  the  privilege  of  purchasing  it  at  the  same  price  pro- 
viding the  total  quantity  does  not  exceed  4  acre-feet  per  share. 

CONTINUOUS  DELIVERY  WASTES  WATER. — A  continuous  flow 
during  the  irrigation  season  may  be  delivered  to  large  farms  with 
only  normal  waste  but  in  the  case  of  small  or  medium-sized 
farms  rotation  should  be  practised  in  the  interests  of  economy. 
The  needs  of  the  average  crop  for  water  vary  greatly  between 
seed  time  and  harvest  and  a  water-right  contract  which  calls  for 
a  continuous  delivery  of  a  fixed  volume  of  water  from  early  spring 
to  late  fall  is  not  only  wrong  in  principle  but  wasteful  of  water. 
Instead  of  a  continuous  flow  water  contracts  might  better  provide 
for  the  delivery  at  stated  periods  during  each  season  of  a  definite 
quantity  of  water  preferably  expressed  in  acre-feet  per  acre.  In 
the  case  of  stored  water,  well  water,  or  other  constant  sources  of 
supply,  the  delivery  might  be  made  on  demand  of  the  user  after 
due  notification.  A  system  of  this  kind  would  insure  the  delivery 
to  the  farmer  of  the  proper  amount  of  water  at  the  right  time. 

OTHER  LOSSES  or  WATER. — The  waste  of  water  caused  by  evapo- 


WASTE,  MEASUREMENT,  AND  DELIVERY      115 

ration  from  irrigated  fields,  deep  percolation,  uneven  distribu- 
tion, poorly  prepared  fields,  imperfect  methods  of  application  and 
unskillful  use,  will  be  treated  under  other  headings. 

27.  Measurement  of  Water. — The  necessity  for  measuring 
the  water  delivered  to  irrigators  is  now  generally  recognized 
throughout  the  arid  region.  While  many  irrigation  enterprises 
still  do  without  such  measurements,  the  increasing  value  of  water 
and  the  gradual  establishment  of  the  principle  that  irrigators 
should  pay  for  the  quantity  of  water  used  rather  than  for  the 
number  of  acres  irrigated  are  forcing  measurements  on  the  well- 
managed  systems.  Above  all,  wise  farm  management  requires 
that  irrigators  should  know  by  actual  measurement  whether 
they  are  receiving  the  water  for  which  they  are  paying  from  50 
cents  to  $20  or  more  per  acre-foot. 

The  measurement  of  water  is  a  large  subject.  To  treat  it 
fully  would  require  a  volume  in  itself.  The  parts  of  the  subject 
herein  considered  will,  therefore,  be  limited  to  a  brief  presentation 
of  those  features  which  concern  the  irrigator  and  more  particularly 
the  devices  and  methods  which  he  can  employ  in  the  purchase, 
delivery  and  use  of  water. 

UNITS  OF  MEASURE. — A  number  of  standard  units  are  used  in 
the  measurement  of  water.  Other  units  and  terms  more  indefi- 
nite in  character  are  likewise  in  common  use  in  certain  localities 
and  both  kinds  are  herein  defined. 

(1)  Cubic  Foot  per  Second. — This  standard  unit,  usually  ab- 
breviated to  second-foot  in  America  and   to   cusec   in  British 
India,  represents  the  quantity  of  water  flowing  through  a  flume 
or  other  channel  1  foot  wide  and  1  foot  deep  with  a  mean 
velocity  of  1  foot  per  second  of  time. 

(2)  Acre-foot. — As  the  term  implies,  an  acre-foot  is  the  volume 
which  will  cover  1  acre  1  foot  in  depth  and  is  equivalent  to 
43,560  cubic  feet.     An  acre-inch  is  one-twelfth  of  an  acre-foot. 

(3)  U.  S.  Gallon.— The  U.  S.  gallon  contains  231  cubic  inches. 
The  three  units  just  described  are  standard  in  this  country 

but  those  which  follow  vary  with  the  state  or  locality. 

(4)  Miner's  Inch. — This  unit  represents  the  quantity  of  water 
which  will  flow  through  an  orifice  1  square  inch  in  area  under  a 
given  head  of  water.     Since  the  head  varies  with  the  prevailing 
custom  of  different  localities,  the  miner's  inch  likewise  varies. 


116  USE  OF  WATER  IN  IRRIGATION 

(5)  Head  of  Water. — The  quantity  of  water  which  is  turned 
into  a  farmer's  supply  ditch  is  usually  termed  a  head.     The  same 
term  is  used  to  designate  the  quantity  used  to  irrigate  a  field. 
While  the  head  of  water  is,  as  a  rule,  quite  uniform  over  any  given 
canal  system  it  varies  between  wide  limits  among  systems  and 
states.     In  Utah  a  head  of  water  is  called  an  "irrigating  stream." 

(6)  An  Irrigation. — Equally  indefinite  is  the  term  " irrigation" 
when  used  to  represent  the  quantity  of  water  applied  to  land  at 
any  one  time.     A  light  irrigation  may  not  exceed  2  acre-inches 
per  acre,  whereas  a  heavy  irrigation  often  exceeds  6  acre-inches 
per  acre. 

UNIT  EQUIVALENTS. — In  converting  from  one  unit  to  another 
the  volumes  carried  in  ditches,  stored  in  reservoirs,  pumped  from 
wells  or  spread  over  the  land,  the  following  table  of  equivalents 
may  be  found  convenient: 

1  cubic  foot  equals  7.48  gallons. 

1  cubic  foot  of  water  weighs  62  1/2  pounds. 

1  second-foot  equals  about  1  acre-inch  per  hour. 

1  second-foot  equals  1.983  acre-feet  per  day. 

1  second-foot  equals  448.8  gallons  per  minute. 

1  second-foot  equals  646,272  gallons  per  day. 

1  acre-foot  equals  43,560  cubic  feet,  equals  325,850  gals. 

1  acre-inch  equals  3630  cubic  feet,  equals  27,154  gallons. 

50  miner's  inches  equal  1  second-foot  in  So.  California,  Idaho,  Kansas, 
New  Mexico,  North  Dakota,  South  Dakota,  Nebraska  and  Utah. 

40  miner's  inches  equal  1  second-foot  in  Central  California,  Arizona, 
Montana  and  Oregon. 

38.4  miner's  inches  equal  1  second-foot  in  Colorado. 

VOLUMETRIC  MEASUREMENT. — Springs,  ditches  or  small  streams 
may  be  diverted  into  a  vessel  of  known  capacity  and  the  discharge 
determined  by  noting  the  time  required  to  fill  the  vessel.  Larger 
flows  may  be  diverted  into  tanks  Or  reservoirs  and  measured  by 
ascertaining  the  cubical  contents  of  that  part  of  the  tank  or  reser- 
voir which  is  either  filled  or  emptied  in  a  given  time. 

WEIRS. — The  weir,  Fig.  51,  is  one  of  the  most  common  devices 
for  the  measurement  of  farm  water  supplies.  It  is  accurate, 
cheap  and  easy  to  install.  Conditions,  however,  are  frequently 
encountered  which  prevent  its  use  or  lessen  its  efficiency.  It 
is  not  a  suitable  device  to  measure  the  water  of  silt-laden  streams 
owing  to  the  rapid  deposit  of  silt  on  the  up-stream  side  of  the 
weir.  In  other  cases  the  grade  of  the  ditch  may  be  too  flat  to 


PLATE  V 


FIG.  A. — Downstream  view  of  trapezoidal  wire  in  use. 


FIG.  B. — Upstream  view  showing  measurement  being  taken. 

(Facing  page  117.) 


PLATE  V 


I 
M 

'So 
£ 


WASTE,  MEASUREMENT,  AND  DELIVERY      117 


permit  of  the  necessary  fall  of  water  from  the  notch.  Even  under 
the  most  favorable  conditions  it  is  liable  to  become  defective 
and  give  inaccurate  results. 

There  are  three  types  of  farmers'  weirs,  rectangular,  trapezoidal, 
and  triangular,  depending  on  the  form  of  weir  notch.  In  measur- 
ing water  accurately  by  the  use  of  any  one  of  these  types,  it  is 
desirable  to  reduce  the  velocity  of  water  to  a  minimum  as  it 
approaches  the  weir.  To  accomplish  this  a  small  pond  is  formed 
on  the  upstream  side  of  the  weir.  This  can  be  done  readily  and 


F.C'S. 


FIG.  51. — Rectangular  weir  showing  pond. 

cheaply  in  earth  as  may  be  seen  from  Plate  V,  Figs.  A  and  B. 
An  automatic  water  register  (Plate  V,  Fig.  C)  is  useful  for  record- 
ing the  height  of  water  flowing  over  the  weir. 

Where  a  slight  error  in  measuring  water  is  permissible  the  weir 
pond  may  be  reduced  in  area  and  a  corresponding  reduction  made 
in  the  dimensions  of  the  weir  box.  This  change  will  be  apt  to 
cause  the  water  to  approach  the"  weir  with  some  velocity  but  if 
this  velocity  does  not  exceed  0.5  foot  per  second  the  results  of  the 
measurement  as  given  in  Table  20  for  Cipolletti  weirs  are  likely 
to  be  sufficiently  accurate  for  farm  supplies. 


118 


USE  OF  WATER  IN  IRRIGATION 


DISCHARGE  OVER  CIPOLLETTI  WEIRS 


Head 

of    water 

1-foot 

weir 

2-foo 

j  weir 

3-foo 

t  weir 

Feet 

Inches 

Cubic 
feet 
per  second 

Gallons 
per 
minute 

Cubic 
feet 
per  second 

Gallons 
per 
minute 

Cubic 
feet 
per  second 

Gallons 
per 
minute 

0.11 

1  3/8 

0.123 

55.3 

0.25 

112.4 

0.37 

161.2 

0.12 

1/2 

0.140 

63.0 

0.28 

125.9 

0.42 

188.8 

0.13 

9/16 

0.158 

71.0 

0.32 

143.8 

0.47 

211.2 

0.14 

5/8 

0.176 

79.2 

0.35 

157.3 

0.53 

238.2 

0.15 

3/4 

0.196 

88.1 

0.39 

175.3 

0.59 

265.0 

0.16 

1  7/8 

0.216 

97.2 

0.43 

193.3 

0.65 

292.1 

0.17 

2 

0.236 

106.1 

0.47 

211.2 

0.71 

319.0 

0.18 

1/8 

0.257 

115.5 

0.51 

229.1 

0.77 

346.0 

0.19 

1/4 

0.279 

125.5 

0.56 

252.0 

0.84 

377.5 

0.20 

3/8 

0.301 

135.2 

0.60 

269.5 

0.90 

404.0 

0.21 

2  1/2 

0.324 

145.5 

0.65 

292.1 

0.97 

436.0 

0.22 

5/8 

0.347 

156.0 

0.69 

310.0 

1.04 

468.0 

0.23 

3/4 

0.371 

166.8 

0.74 

332.5 

1.11 

499.0 

0.24 

7/8 

0.396 

178.0 

0.79 

355.0 

1.19 

535.0 

0.25 

3 

0.421 

189.1 

0.84 

377.5 

1.26 

567.0 

0.26 

31/8 

0.446 

200.5 

0.89 

400.0 

1.34 

602.5 

0.27 

1/4 

0.472 

212.0 

0.94 

422.0 

1.42 

638.0 

0.28 

3/8 

0.499 

224.5 

1.00 

450.0 

1.50 

674.0 

0.29 

1/2 

0.526 

236.5 

.05 

472.0 

1.59 

711.0 

0.30 

5/8 

0.553 

249.0 

•11 

499.0 

1.66 

746.0 

0.31 

3  3/4 

0.581 

261.1 

.16 

522.0 

1.74 

782.0 

0.32 

7/8 

0.609 

274.0 

.22 

548.0 

1.83 

823.0 

0.33 

4 

0.638 

287.0 

.28 

576.0 

1.91 

858.0 

0.34 

1/8 

0.667 

300.0 

1.33 

598.0 

2.00 

899.0 

0.35 

1/4 

0.697 

313.0 

1.39 

625.0 

2.09 

940.0 

0.36 

43/8 

0.727 

327.0 

1.45 

652.0 

2.18 

980.0 

0.37 

1/2 

0.758 

341.0 

1.52 

683.0 

2.27 

1020.0 

0.38 

9/16 

0.789 

354.5 

1.58 

711.0 

2.37 

1065.0 

0.39 

5/8 

0.820 

368.7 

1.64 

737.0 

2.46 

1106.0 

0.40 

3/4 

0.852 

383.0 

1.70 

764.0 

2.56 

1151.0 

0.41 

4  7/8 

0.884 

397.0 

1.77 

796.0 

2.65 

1191.0 

0.42 

5 

0.916 

412.0 

1.83 

822  .  0 

2.75 

1238.0 

0.43 

1/8 

0.949 

426'.  0 

1.90 

854.0 

2.85 

1282.0 

0.44 

1/4 

0.983 

442.0 

1.97 

885.0 

2.95 

1326.0 

0.45 

3/8 

1.016 

455.5 

2.03 

912.0 

3.03 

1370.0 

WASTE,  MEASUREMENT,  AND  DELIVERY      119 


DISCHARGE  OVER  CIPOLLETTI  WEIRS. — Continued 


Head  of  water 

1-foot  weir 

2-foot  weir 

3-foot  weir 

Feet 

Inches 

Cubic 
feet 
per  second 

Gallons 
per 
minute 

Cubic 
feet 
per  second 

Gallons 
per 
minute 

Cubic 
feet 
per  second 

Gallons  j 
per 
minute 

0.46 
0.47 
0.48 
0.49 
0.50 

0.51 
0.52 
0.53 
0.54 
0.55 

0.56 
0.57 
0.58 
0.59 
0.60 

0.61 
0.62 
0.63 
0.64 
0.65 

0.66 
0.67 
0.68 
0.69 
0.70 

0.71 
0.72 
0.73 
0.74 
0.75 

51/2 

5/8 
3/4 
7/8 
6 

1/8 
1/4 
3/8 
1/2 
5/8 

63/4 

7/8 
7 
1/8 
1/4 

73/8 
1/2 
9/16 

5/8 
3/4 

77/8 
8 
1/8 
1/4 
3/8 

81/2 
5/8 
3/4 
7/8 
9 

.050 
.085 
.120 
.155 
.190 

472.0 

487.5 
504.0 
519.0 
535.0 

2.10 
2.17 
2.24 
2.31 
2.38 

2.45 
2.52 
2.60 
2.67 
2.75 

2.82 
2.90 
2.97 
3.05 
3.13 

3.21 
3.29 
3.37 
3.45 
3.53 

3.61 
3.69 
3.78 
3.86 
3.94 

4.03 
4.11 
4.20 
4.29 
4.37 

944.0 

976.0 
1008.0 
1038.0 
1070.0 

1101.0 
1132.0 
1169.0 
1200.0 
1235.0 

1268.0 
1303.0 
1335.0 
1371.0 
1408.0 

1441.0 
1480.0 
1515.0 
1550.0 
1587.0 

1622.0 
1659.0 
1700.0 
1735.0 
1771.0 

1815.0 
1850.0 
1888.0 
1930.0 
1965.0 

3.15 
3.25 
3.36 
3.46 
3.57 

3.68 
3.79 
3.90 
4.01 
4.12 

4.23 
4.35 
4.46 
4.58 
4.69 

4.81 
4.93 
5.05 
5.17 
5.29 

5.42 
5.54 
5.66 
5.79 
5.92 

6.04 
6.17 
6.30 
6.43 
6.56 

1412.0 
1460.0 
1511.0 
1555.0 
1605.0 

1655.0 
1695.0 
1753.0 
1800.0 
1850.0 

1905.0 
1955.0 
2005.0 
2060.0 
2109.0 

2160.0 
2220.0 
2270.0 
2322.0 
2380.0 

2435.0 
2490.0 
2545.0 
2602.0 
2660.0 

2715.0 
2771.0 
2830.0 
2892.0 
2850.0 



THE  MINER'S  INCH. — This  method  of  measuring  water  was  in 
common  use  in  the  West  during  the  early  mining  period  and 
under  the  conditions  which  then  prevailed  it  was  probably  the 
best  that  could  be  devised.  Since,  however,  it  can  be  used  only 


120  USE  OF  WATER  IN  IRRIGATION 

to  measure  small  streams,  its  use  for  this  and  other  reasons  has 
now  become  restricted  to  a  few  localities.  Formerly  each  mining 
camp  adopted  its  own  standard  "inch"  but  in  more  recent  times 
nearly  all  the  local  standards  have  been  combined  into  two  kinds. 
In  one  of  these  the  depth  or  head  of  water  above  the  center  of  the 
opening  is  4  inches  and  in  the  other  it  is  6  inches.  The  opening 
is  usually  2  inches  measured  vertically.  In  the  first-named 
kind,  if  the  slide  which  controls  the  opening  is  pulled  out  so  as  to 
leave  an  opening  2  inches  vertical  by  25  inches  horizontal,  the 
discharge  would  be  50  miner's  inches  or  an  equivalent  of  1  second- 
foot.  In  the  last-named  kind,  owing  to  the  greater  head,  if  the 
slide  is  pulled  out  20  inches  so  as  to  leave  an  opening  2  X  20 
inches  the  discharge  would  be  40  miner's  inches  or  an  equivalent 
of  1  second-foot. 

SUBMERGED  OKIFICE. — Water  may  be  measured  as  it  passes 
through  a  submerged  opening  in  a  gate  or  other  structure  by 
ascertaining  the  difference  in  elevation  of  the  water  surface  on 
each  side  of  the  gate  and  adopting  the  proper  coefficient  of  dis- 
charge through  the  opening.  The  former  is  readily  obtained  but 
the  latter  usually  varies  with  each  structure  installed.  In  some 
types  of  submerged  orifices  an  attempt  is  made  to  provide  con- 
traction on  the  bottom  and  sides  of  the  opening  but  a  contraction 
on  the  bottom  soon  fills  with  debris  or  sediment  and  this  change 
in  condition  causes  an  over-registration  of  water. 

Another  frequent  cause  of  error  in  this  form  of  measuring 
device  is  due  to  the  fact  that  the  water  may  approach  the  open- 
ing with  more  or  less  velocity  which  likewise  causes  an  over- 
registration. 

A  gate  or  box  containing  a  submerged  opening  should  be  so 
planned  and  installed  that  there  would  be  complete  contraction 
on  each  side  but  no  contraction  on  the  bottom.  The  velocity 
of  approach  should  also  be  eliminated  as  far  as  practicable  and 
the  whole  device  standardized,  so  as  to  cause  the  least  change  in 
conditions  while  in  use.  The  discharge  in  second-feet  may  be 
computed  from  the  equation  Q  =  CA  V2  gh  where  Q  is  the  dis- 
charge in  second-feet,  C  a  constant  ranging  from  0.65  to  0.85,  A 
the  area  of  the  orifice  in  square  feet,  g  the  acceleration  of  gravity 
in  feet  per  second  and  h  the  head  in  feet. 

This  mode  of  measuring  water  used  in  irrigation  is  well  adapted 


WASTE,  MEASUREMENT,  AND  DELIVERY      121 


to  silt-hulcii  water  supplies  and  to  localities  with  insufficient  fall 
to  justify  the  installation  of  weirs. 

PROPORTIONAL  DIVISION  OF  WATER. — In  some  states,  notably 
I'tah,  not  only  the  water  carried  by  canals  but  also  the  dis- 
charge of  the  smaller  strealns  is  frequently  allotted  to  the  users 
in  proportional  parts  of  the  entire  flow.  The  basis  of  allotment 
is  the  number  of  shares  of  stock  owned  by  each  user,  each  share 
usually  representing  an  acre  of  irrigable  land.  Since  western 
streams  and  to  a  considerable  extent  western  gravity  canals  are 
subject  to  wide  fluctuations  in  the  volumes  carried,  there  is  a 


Note: 
Gate  to  be 
Hinged 
this  Post 


FIG.  52. — Design  for  proportional  division  box. 

decided  advantage  in  using  this  method.  Its  chief  defect  is  due 
to  a  disregard  of  transmission  losses  which  results  in  allotting  too 
much  water  to  the  upper  users  of  a  system  and  too  little  to  the 
1<  »\ver  users.  An  equitable  apportionment  of  the  available  or  net 
flow  can  be  effected  only  by  first  deducting  all  losses  due  to  trans- 
mission and  this  method  requires  the  measurement  rather  than 
the  proportioning  of  water. 

The  division  box  shown  in  Fig.  521  is  based  on  the  principle  that 

1  Gate  Structures  for  Irrigation  Canals,  by  Fred  C.  Scobey.    U.  S.  De- 
partment of  Agriculture,  Bui.   115. 


122 


USE  OF  WATER  IN  IRRIGATION 


water  flows  over  a  weir  crest  in  volumes  proportionate  to  its  length 
providing  certain  conditions  are  complied  with.  These  are  (a) 
that  the  velocity  of  water  above  the  weir  and  before  it  is  in- 
fluenced by  it  is  quite  low;  (b)  that  the  crest  board  be  set  far- 
enough  downstream  in  the  flume  so  as  to  insure  complete  side 
contractions;  (c)  that  the  influence  of  backwater,  if  any,  be  uni- 
form across  the  box  and  (d)  that  the  crest  be  kept  level. 

The  division  of  water  by  means  of  such  boxes  can  best  be 
described  by  an  example.  At  a  certain  box  delivering  water  to 
John  Smith  there  are  84  shares  including  Smith's  yet  to  be  served. 
The  width  of  the  water  channel  is  60  inches  which  is  reduced  to  a 
net  width  of  58  inches  by  deducting  the  width  of  the  division 
board.  Mr.  Smith  has  17  shares  of  stock  and  the  width  of  the 
crest  serving  his  ditch  would  therefore  be  found  by  the  following 
proportion. 

Smith's  crest  in  inches       17 

-  =  o7  =  10.75  inches 


58 


84 


TIME-FLOW  METHOD. — When  a  constant  stream  of  water  whose, 
volume  has  been  measured,  is  turned  into  a  lateral  ditch  or  pipe 


FIG.  53. — Venturi  irrigation  meter. 

the  simplest,  cheapest  and  most  accurate  means  of  ascertaining 
the  quantity  delivered  to  each  irrigator  who  uses  it  in  turn  is  to 
keep  a  record  of  the  time  of  flow  to  each.  For  lack  of  a  better 
term  the  writer  ha/3  called  this  the  time-flow  measurement. 
Where  irrigation  water  is  distributed  under  pressure  through 
lateral  pipes  the  special  Venturi  meter  shown  in  Fig.  53  adapted 
to  such  conditions  can  be  installed  at  the  head  of  each  lateral  line. 
Where  an  open  ditch  is  used  the  water  entering  the  ditch  can  be 
measured  by  a  weir  or  other  device.  In  this  way  all  deliveries 


WASTE,  MEASUREMENT,  AND  DELIVERY      123 

to  users  on  the  same  lateral  whether  through  a  pipe  or  ditch  can 
be  made  by  the  time-flow  method. 

CURRENT  METER. — The  current  meter  is  a  light  portable  device 
for  measuring  the  rate  of  flow  of  water  and  consists  of  a  screw 
propeller  or  cup-shaped  wheel  delicately  mounted  so  that  even 
a  sluggish  current  will  cause  either  to  revolve.  Each  complete 
revolution  of  the  meter  or  a  fixed  number  of  revolutions  is  noted 
by  a  click  which  is  transmitted  to  the  ear  of  the  operator  by  a 
sounding  tube  or  electrical  connection.1 

It  is  obvious  that  the  faster  the  water  flows  the  greater  will  be 
the  number  of  revolutions  of  the  meter  and  that  each  revolution 
will  indicate  a  certain  rate  of  flow  in  the  water.  The  determina- 
tion of  this  relation  is  called  " rating  the  meter."  If  all  meters 
of  the  same  type  revolved  with  the  same  ease  and  speed  under 
similar  conditions  the  manufacturer  could  ship  with  each  new 
instrument  the  standard  rating  for  that  type.  Numerous  tests 
have  shown,  however,  that  no  two  meters  behave  exactly  alike 
and  for  accurate  work  each  has  to  be  rated.  A  rating  station 
has  been  established  by  the  Bureau  of  Standards  near  Washing- 
ton, D.  C.,  and  other  stations  are  to  be  found  in  various  parts  of 
the  West.  The  meter  when  being  rated  is  attached  by  a  rod  to 
a  car  on  a  track  and  is  held  about  1  foot  deep  in  still  water. 
The  car  is  then  moved  over  a  measured  course  at  speeds  ranging 
from  0.2  to  10  feet  per  second  and  over,  an  accurate  record  being 
kept  of  the  time  and  the  number  of  revolutions.  From  the  results 
of  a  sufficient  number  of  runs  a  table  is  computed  which  gives 
the  rating  of  the  meter  within  the  range  of  the  observations. 

Water  flowing  under  normal  conditions  in  any  ditch  or  canal 
has  a  relatively  high  velocity  at  the  center  and  a  slow  velocity  at 
either  side  and  along  the  bottom.  In  order  to  obtain  the  average 
velocity  it  is  necessary  to  determine  the  speed  of  the  water  at 
various  points  or  in  various  sections.  The  usual  practice  is  to 
select  a  suitable  part  of  a  straight  channel  having  a  smooth  and 
uniform  section  in  which  the  velocity  of  the  water  is  slow  rather 
than  fast.  An  ideal  velocity  is  about  2  feet  per  second.  A  plank 
or  timber  may  be  placed  across  the  channel,  Fig.  54,  and  the  width 

1  For  detailed  description  of  current  meter  see  River  Discharge  by  Hoyt 
and  Grover,  John  Wiley,  New  York,  Publisher. 


124 


USE  OF  WATER  IN  IRRIGATION 


of  the  water-surface  marked  thereon  in  feet.  Beginning  at 
station  zero  as  shown  on  the  plank,  ascertain  the  depth  and  mean 
velocity  at  station  0.25,  and  afterward  at  stations  1,  2,  3,  etc. 
The  depth  in  feet  at  stations  1,  2,  3,  etc.,  multiplied  by  the  mean 
velocity  in  feet  per  second,  will  give  the  flow  for  that  particular 
station  in  cubic  feet  per  second  and  the  sum  of  all  these  products 
will  represent  the  discharge  of  the  ditch,  with  the  exception  of 
what  flows  through  the  small  areas  at  each  side.  The  small  area 
between  stations  zero  and  0.5  is  considered  as  a  triangle  and  its 
discharge  computed.  The  fractional  part  of  a  station  at  the 


FIG.  54. — Measuring  a  canal  with  current  meter. 

other  edge  of  the  water-surface  is  similarly  treated,  thus  complet- 
ing the  total  discharge. 

In  determining  the  mean  velocity  of  any  vertical  section  the 
integration  method  is  recommended  for  small  ditches  and  streams. 
This  consists  in  moving  the  meter  vertically  from  just  below  the 
surface  of  the  water  to  the  bottom  of  the  ditch  and  back  again 
to  the  surface,  repeating  the  operation  as  often  as  necessary, 
taking  note  of  the  time  by  a  stop-watch,  and  counting  the  revo- 
lutions of  the  meter  in  the  entire  period.  In  using  this  method, 
care  should  be  exercised  to  move  the  meter  very  slowly  and  uni- 
formly through  the  water,  so  as  to  secure  the  average  of  the  differ- 
ent velocities  in  any  vertical  section. 


WASTE,  MEASUREMENT,  AND  DELIVERY      125 

SLOPE  FORMULAE. — In  estimating  the  capacity  of  a  dry  ditch  or 
one  which  is  only  partially  filled,  Kutter's  formula  may  be  used. 
In  applying  this  formula  it  is  advisable  to  determine  the  grade 
or  fall  of  the  ditch  over  at  least  500  feet,  and  to  apply  the  average 
grade  thus  found  to  a  particular  section.  The  sectional  area, 
\\vttod  perimeter,  and  coefficient  of  roughness  for  this  section 
being  next  determined,  the  velocity  and  discharge  may  be  com- 
puted from  the  known  hydraulic  elements. 

AUSTRALIAN  METER. — Most  farmers  prefer  a  measuring  device 
which  records  the  quantity  of  water  delivered  in  some  well-known 
unit.  Such  a  meter  has  been  devised  by  Mr.  Dethridge,  an  engi- 
neer of  Australia  where  it  is  in  common  use.  It  consists  of  a 
metal  drum  about  28  inches  in  diameter  to  which  are  attached 
V-shaped  blades  of  the  same  material  10  inches  in  length.  The 
drum  carrying  the  blades  revolves  in  a  concrete  flume  about 
30  inches  wide,  the  middle  portion  of  the  bottom  being  con- 
cave to  fit  the  revolving  wheel.  One-fourth  of  an  inch  clear- 
ance is  allowed  on  sides  and  bottom.  Each  pocket  between  the 
projecting  blades  must  be  filled  with  water  before  the  wheel 
revolves  and  the  automatic  recording  device  attached  to  the 
axle  of  the  drum  indicates  the  volume  of  water  delivered. 

Fig.  A  of  Plate  VI  shows  one  of  these  meters  being  tested 
against  a  standard  weir  on  the  University  farm  at  Davis,  Cali- 
fornia. Fig.  B  of  the  same  plate  shows  a  meter  of  this  type  in 
operation  in  the  State  of  Victoria,  Australia.1 

28.  Evaporation  from  Water  Surfaces. — Evaporation  from 
water  surfaces  is  of  importance  to  the  irrigation  engineer  in  con- 
nection with  the  loss  from  reservoirs  and  to  a  very  small  degree  in 
connection  with  the  loss  from  canals.  It  is  also  of  importance 
to  the  irrigation  farmer  because  it  gives  some  indication  of  the 
loss  from  the  surface  of  irrigated  soils  discussed  in  Art.  29. 

APPLIANCES  USED. — Evaporation  from  water  surf  aces  is  usually 
ascertained  by  measuring  the  depth  lost  from  evaporating  pans 
or  tanks  freely  exposed  to  the  weather  and  set  in  the  ground  with 
the  earth  compactly  replaced  about  them  and  with  the  rims  of  the 
pans  or  tanks  protruding  about  1  inch  above  the  ground.  It 
is  generally  customary  to  use  round  tanks  made  of  galvanized 
sheet  iron  and  varying  in  diameter  from  2  to  8  feet  and  in  depth 

1  See  report  for  1913,  Western  Canada  Irrigation  Association. 


126  USE  OF  WATER  IN  IRRIGATION 

from  2  to  3  feet,  a  round  tank  4  feet  in  diameter  and  2.5  feet  deep 
being  suggested  as  a  desirable  standard.1 

Additional  equipment  for  ordinary  observation  consists  of  a 
hook  gauge  for  measuring  weekly  or  daily  loss,2  and  a  standard 
rain  gauge  for  measuring  precipitation  between  observations  and 
refillings  of  the  evaporation  tank.  For  complete  engineering 
observation  there  should  be  added  a  set  of  maximum  and  mini- 
mum thermometers  and  a  standard  psychrometer  for  ascertaining 
the  dew  point,  and  also  an  anemometer  for  ascertaining  wind 
movement.  The  latter  instruments  are  only  needed  when  it  is 
desired  to  apply  observed  data  to  situations  considerably  removed 
from  the  place  of  observation.3  The  entire  equipment  should  be 
protected  from  stray  animals  by  a  low  wire-mesh  fence. 

How  EVAPORATION  is  DETERMINED. — When  feasible  it  is  desir- 
able to  record  evaporation  not  less  frequently  than  once  weekly 
and  daily  observations  for  short  periods  at  intervals  during  the 
observational  period  are  often  desirable.  When  starting  ob- 
servations the  tank  should  be  filled  to  within  1  to  3  or  4  inches 
of  the  top,  depending  on  the  size  of  the  tank  and  the  prevalence 
of  winds,  these  two  factors  determining  possible  slopping  over 
the  rim  of  the  tank  by  wave  action.  During  periods  of  possible 
excessive  precipitation  the  water  must  be  kept  a  safe  distance  be- 
low the  rim,  daily  observations  often  being  necessary  to  insure 
this  result.  A  desirable  plan  is  to  fill  the  tank  at  each  re-filling 
to  the  same  depth.  To  the  measured  loss  should  be  added  at 
each  observation  the  precipitation  since  the  last  observation.  It 

1  Experiments  by  the  U.  S.  Weather  Bureau,  reported  in  the  Monthly 
Weather  Review,  February  and  July,  1910,  pp.  307,  1133,  indicate  a  sen- 
sible difference  in  the  evaporation  from  vessels  of  different  diameters,  so 
that  careful  calculations  of  evaporation  from  observed  data  must  neces- 
sarily take  into  account  the  sizes  of  vessels  used  in  observations.     As 
observed  data  regarding  evaporation  losses  are  often  made  general   use 
of  in  engineering  practice  the  need  of  a  standard  vessel  is  obvious. 

2  A  recording  evaporimeter  for  obtaining  continuous  records  is  a  valuable 
addition  to  the  equipment.     For  description  of  an  evaporimeter  used   by 
the   Irrigation   Investigations   of  the   U.   S.    Department  of   Agriculture, 
See  U.  S.  D.  A.,  O.  E.  S.  Bui.  No.  248. 

3  A  much  more  elaborate  equipment  is  used  in  observations  and  experi- 
ments designed  to  furnish  data  of  wide  scientific  application.     For  descrip- 
tion of  such  equipment  see  Monthly  Weather  Review,  Feb.  and  Dec.,  1910, 
pp.  307,  1133. 


PLATE  VI 


FIG.  A. — Testing  Australian  meter  against  standard  weir. 


FIG.  B. — Similar  device  used  in  Victoria,  Australia. 

(Facing  page  125.) 


WASTE,  MEASUREMENT,  AND  DELIVERY      127 

is  not  necessary  that  the  tank  should  be  re-filled  after  each  ob- 
servation, yet  a  variation  in  the  water  level  of  more  than  3  or  4 
inches  should  not  be  permitted. 

FACTORS  GOVERNING  EVAPORATION. — What  determines  the  rate 
of  evaporation  from  freely  exposed  water  surfaces  has  been  ex- 
tensively studied,  some  of  the  most  complete  technical  work  done 
along  this  line  in  this  country  being  that  of  Fitzgerald  and  the 
U.  S.  Weather  Bureau.1  The  governing  factor  in  evaporation 
is  the  temperature  of  the  water,  which  is  of  course  dependent  on 
the  temperature  of  the  atmosphere  immediately  above,2  evapora- 
tion taking  place  more  rapidly  when  the  surface  water  tempera- 
ture is  considerably  above  the  dew  point  of  the  surrounding  air. 
Other  factors  are  air  movement  above  the  water  surface,  humidity, 
and  possibly  to  some  extent  altitude.  Air  movement  above 
a  water  surface  increases  evaporation  to  the  extent  that  drier  air 
is  made  to  replace  the  air  already  charged  with  the  escaping  vapor 
from  the  water  surface,  for  at  any  given  temperature  air  is  capable 
of  holding  only  a  definite  amount  of  moisture,  saturation  occur- 
ring when  that  quantity  is  supplied.  It  has  been  found  that 
while  evaporation  is  greatly  reduced  during  foggy  weather,  it 
does  not  altogether  cease  even  with  a  saturated  atmosphere 
provided  there  is  air  movement  above.  The  effect  of  altitude 
merely  in  so  far  as  concerns  change  in  barometric  pressure,  is 
not  yet  fully  established,  although  most  observers  credit  it  with 
exerting  but  little  influence,  and  limited  experiments  of  the  U.  S. 
Weather  Bureau  point  to  not  greater  evaporation  at  4000  feet 
elevation,  after  correction  for  temperature,  etc.,  than  at  sea  level. 

1  For  account  of  the  work  of  Fitzgerald  see  Trans.  Am.  Soc.  Civil  Eng., 
Vol.  XV,  pp.  581  et  seq.     For  account  of  investigations  of  U.  S.  Weather 
Bureau  see  Monthly  Weather  Review,  Feb.  and  July,  1910,  pp.  307,  1133. 
For  additional  miscellaneous  references  see  among  many  others,  Quart.  Jr. 
Royal  Met.  Soc.  (Eng.),  Vol.  XVIII,  pp.  54  et  seq,  Bui.  45,  Colo.  Agr.  Exp. 
Sta.:  Eng.  News.  Apr.  6,  1905,  p.  353;  Sept.  19,  1907,  p.  304;  Aug.  13,  1908, 
p    !•»:{;  Trans.  Am.  Soc.  Civil  Eng.,  Vol.  LXXVI,  p.  1516;  U.  S.  Dept.  Agr. 
O.  E.  S.,  Bui.  177,  Eng.  Rec.,  Feb.  12,  1910,  p.  198,  U.  S.  Dept.  Agr.  B.  P.  I., 
Bui.    188.     For  an  extended   bibliography   on  evaporation  see   Monthly 
Weather  Review  for  1908  and  1909. 

2  For  results  of  experiments  on  the  effect  of  water  temperature  on  evapora- 
tion, especially  in  its  relation  to  irrigation  practice,  see  U.  S.  Dept.  Agr. 
O.  E.  S.Buls.  177  and  248. 


128  USE  OF  WATER  IN  IRRIGATION 

UNITED  STATES  EVAPORATION  RECORDS. — Evaporation  losses 
from  small  tanks  or  pans  have  been  widely  observed  in  the  United 
States  and  table  No.  21  gives  the  observed  monthly  and  annual 
rates  for  various  localities,  records  from  evaporation  tanks  or 
pans  situated  on  or  near  the  ground  chiefly  being  drawn  from. 
The  pans  used  in  the  observations  reported  have  varied  from  2  to 
6  feet  in  diameter  and  have  been  mostly  set  into  the  ground.1 
Measurements  of  evaporation  from  large  bodies  of  water  have 
been  very  limited  and  are  extremely  difficult  to  make,  owing 
largely  to  the  uncertainties  of  underground  increase  or  loss,  as 
well  as  increase  from  surface  run-off.  Observations  of  the  U.  S. 
Weather  Bureau  at  Salton  Sea  have  added  to  the  available  data 
on  the  subject  by  showing  that  evaporation  from  large  bodies  of 
water  is  only  between  60  and  70  per  cent,  of  that  observed  from 
experimental  tanks.  In  applying  to  reservoirs  a*nd  other  large 
bodies  of  water  data  obtained  from  small  evaporating  tanks  or 
pans  this  correction  should  therefore  be  made.  In  estimating 
evaporation  losses  from  reservoirs  it  should  be  further  borne  in 
mind  that  owing  to  the  higher  temperature  of  their  water,  shal- 
low bodies  evaporate  more  water  than  deep  bodies,  also,  that 
thus  far  there  has  not  been  found  an  appreciable  difference  be- 
tween the  amount  evaporated  near  the  shore  of  lakes  and  reser- 
voirs and  at  some  distance  from  the  shore. 

29.  Evaporation  from  Irrigated  Soils. — Investigations  to  de- 
termine the  rate  of  evaporation  from  irrigated  soils  have  been 
carried  on  for  a  number  of  years  by  the  Office  of  Experiment 
Stations,  U.  S.  Department  of  Agriculture,  under  the  supervision 
of  the  writer  and  summaries  of  the  results  obtained  have  been 
published  in  Buls.  177  and  248  of  the  Office.  From  these  the 
following  data  are  taken. 

1  The  records  given  for  Mecca  and  Lake  Tahoe,  Cal.;  Deer  Flat,  Idaho; 
Fallon,  Nev.;  Carlsbad,  N.  M.;  Ady,  Oregon;  and  North  Yakima,  Wash- 
ington, are  the  records  of  the  U.  S.  Weather  Bureau  (Vol.  LXIII,  Eng.  News, 
p.  694)  and  contain  interpolations  for  from  3  to  7  months.  The  early 
records  for  California  are  from  Physical  Data  and  Statistics,  1886,  and 
the  later  records  are  mainly  from  reports  of  Irrigation  Investigations 
O.  E.  S.,  U.  S.  D.  A.  Other  records  are  mainly  from  the  reports  and  bulle- 
tins of  the  state  experiment  stations.  Reports  of  the  Irrigation  Investi- 
gations and  the  various  state  experiment  stations  give  a  large  number  of 
part-season  records. 


WASTE,  MEASUREMENT,  AND  DELIVERY      129 


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130 


USE  OF  WATER  IN  IRRIGATION 


The  equipment  (Fig.  55  and  Plate  VII)  consisted  of  large 
double  tanks  of  galvanized  iron  and  suitable  apparatus  for  weigh- 
ing the  soil  in  each  vessel.  The  outer  tanks  were  installed  nearly 
level  with  the  ground  surface  in  a  field  or  orchard  and  the  an- 
nular space  between  the  outer  and  inner  tanks  of  each  set  was 
filled  with  water.  In  filling  the  inner  tank  with  soil,  care  was 
taken  to  place  it  within  the  tank  in  its  natural  condition. 

AMOUNT  EVAPORATED  . — 
The  results  of  the  experiments 
conducted  at  Riverside,  Cali- 
fornia, showed  that  when  the 
dry  sandy  loam  of  an  orchard 
was  irrigated  by  the  furrow 
method,  the  average  loss  by 
evaporation  during  a  subse- 
quent period  of  5  days  was  15 
per  cent,  of  the  water  applied 
in  irrigation. 

In  other  experiments  at  the 
same  place  the  loss  by  evapo- 
ration in  10  days  after  the 
surface  had  been  irrigated  by 
flooding  ranged  from  21  per 
cent,  to  40  per  cent,  of  the 
amount  of  water  applied. 

At  Davis,  California,  soils 
which  were  irrigated  by  flood- 
ing lost  in  21  days  from  23  per 
cent,  to  40  per  cent,  of  the  volume  applied.  At  Reno,  Nevada, 
similar  losses  during  a  like  period  were  found  to  be  24  per  cent, 
of  the  volume  applied. 

The  investigations  demonstrated  that  the  same  factors  which 
influenced  the  rate  of  evaporation  from  a  water  surface  (Art.  28) 
were  also  applicable  to  soils.  In  the  case  of  soils,  however,  the 
main  governing  factor  in  the  rate  of  evaporation  is  not  the  tem- 
perature of  the  soil  and  air,  the  movement  of  wind,  or  the  humid- 
ity of  the  atmosphere  but  the  percentage  of  moisture  in  the  top 
layer  of  soil.  This  is  illustrated  in  Fig.  56.  It  is  further  shown 
in  Table  22  in  which  the  weekly  rates  of  evaporation  from  soil 


FIG.  55. — Design  of  tank  used  in 
evaporation  experiments. 


WASTE,  MEASUREMENT,  AND  DELIVERY      131 


and   water  surfaces  may  be  compared  under  the  same  climatic 
conditions. 

TABLE  No.  22 
Evaporation  from  Soil  and  Water 


Kind  of  soil  and  percentage 
of  free  water 

Mean   temperature    taken    morning, 
noon  and  evening  in  degrees  F. 

Weekly 
evaporation 

Air  in 
shade 

Soil  in 
shade 

Soil  in 
sun 

Moist 
soil 

Surface 
of  water 

Soil, 
inches 

Water, 
inches 

Sandy  loam  —  saturated  .  .  . 
Sandy  loam  —  17.5  
Sandy  loam  —  11  9 

71 

76 
76 
76 
76 

76 

78 
78 
78 
78 

95 
106 
106 
108 

108 

83 

77 
80 
80 

80 
80 

4.75 
1.33 
1.13 

0.88 
0.25 

1.88 
1.94 
1.94 
1.94 
1.94 

Sandy  loam  —  8.9  

Sandy  loam  —  4.8  

The  investigations  likewise  demonstrated  that  the  loss  by 
evaporation  from  newly  irrigated  soils,  particularly  when  the 
entire  surface  is  moistened  was  very  great  for  the  first  few  days 
after  irrigation.  One  would  expect  this  result  from  what  was 
stated  previously. 


1  and  3 


2  and  4 


5  and  7 


6  and  S 


Loss  by  Evaporation 

Free  Moisture  in  Soil 

rrigation  Water 


234567 
Free  Moisture-Equivalent  in  Depth  over  Surface 


10 


FIG.  56. — Diagram  showing  the  initial  amount  of  free  moisture  in  the 
soil,  the  amount  added,  and  the  loss  by  evaporation,  July  27  to  Aug.  5,  1907, 
at  Riverside,  Cal. 

PARTIAL  PREVENTION  OF  EVAPORATION  LOSSES. — In  all  crops 
the  husbandman  can  materially  lessen  the  amount  of  water  lost  by 
evaporation  by  properly  preparing  the  surface  of  fields,  adopting 
the  right  method  of  applying  water  and  cultivating  the  soil  at  the 
right  time.  In  following  this  course  he  will  not  only  economize 


132 


USE  OF  WATER  IN  IRRIGATION 


in  water  but  will  increase  the  quantity  and  quality  of  the  products 
raised.  The  foregoing  applies  in  particular  to  all  cultivated  and 
deep-rooted  crops  and  for  these  the  following  remedies  for  such 
losses  may  be  applied. 

(a)  Soil  Mulches. — At  five  stations  throughout  the  arid  region 
tanks  (Fig.  55)  containing  soil  were  each  irrigated  to  a  depth  of 
6  inches.  After  the  water  had  entirely  disappeared  from  the 
soil  surface,  fine  dry  granular  soil  mulches  were  added  as  follows : 
Tanks  1  and  2,  no  mulch;  tanks  3  and  4,  a  3-inch  layer;  tanks 


FIG.  57. — Average  evaporation  loses  from  tanks  of  soil  protected  by 
mulches  of  different  depths  during  first  21  days  after  irrigation.  Average 
loss  at  five  stations. 

5  and  6,  a  6-inch  layer;  tanks  7  and  8,  a  9-inch  layer.  Weighings 
were  started  immediately  and  continued  semi-weekly  for  a  period 
of  21  days.  The  average  losses  of  water  at  the  five  stations 
are  shown  graphically  in  Fig.  57. 

(6)  Cultivation. — Similar  equipment  was  used  to  determine 
the  effect  of  cultivation  in  checking  evaporation.  The  results 
of  experiments  conducted  at  six  stations  throughout  the  arid 
region  with  the  accompanying  meteorological  data  are  given 
in  Fig.  58.  The  average  losses  shown  by  the  above  are  2.13 
inches  from  the  uncultivated  and  1.58  inches  from  the  cultivated 
soils,  being  35.5  and  26.3,  respectively,  of  the  total  6  inches  used 
in  irrigation.  It  is  a  significant  fact  that  51  per  cent,  of  the  loss 


WASTE,  MEASUREMENT,  AND  DELIVERY      133 


from  the  cultivated  surface  occurred  in  the  first  3  days,  that 
is,  during  the  average  period  between  irrigation  and  cultivation. 


246      8     10    12     14     16    18 
Days 


FIG.  58. — Average  evaporation  losses  from   cultivated   and   uncultivated 
tanks  during  first  28  days  after  irrigation.     Average  of  losses  at  six  stations. 


Average  of  Two  28-Day  Periods 
July  8-August5  :  August  ID-September? 


1.00 


.'Jo 


3-Inch       G-Inch      9-Inch 
Flooded   Furrows    Furrows  Furrow: 


24     6      8    10    12   14   1C  18   20    22   24  26 
Days 


FIG.  59. — Average  evaporation  losses  from  tanks  irrigated  by  flooding 
and  with  furrows  of  different  depths  at  Reno,  Nevada,  July  8  to  Aug.  5 
and  Aug.  10  to  Sept.  7,  1909. 

This  emphasizes  the  necessity  of  early  cultivation,  especially 
in  the  heavy  soils  where  the  percolation  of  moisture  through  the 
soil  is  slow  and  the  moisture  content  of  the  surface  soil  is  high. 


134 


USE  OF  WATER  IN  IRRIGATION 


The  observations  also  revealed  a  tendency  in  light  sandy  soils 
for  the  uncultivated  surfaces  to  mulch  themselves  and  after  the 
first  few  days  following  the  application  of  water  the  loss  dimin- 
ished very  rapidly  and  in  the  end  little  advantage  is  shown  in 
favor  of  cultivation.  It  not  infrequently  happens  too,  that  the 
cultivation  of  soils  containing  a  high  percentage  of  free  water 
increases  rather  than  diminishes  the  loss  by  evaporation. 

(c)  Shallow  Versus  Deep  Furrows. — Of  late  years  in  orchard 
irrigation  in  particular,  where  the  furrow  method  is  used,  there 
has  been  a  growing  tendency  toward  fewer  and  deeper  furrows 
with  one  heavy  irrigation  every  4  to  6  weeks  rather  fhan  a  larger 
number  of  shallow  furrows  with  a  light  irrigation  at  short  inter- 
vals. In  shallow-rooted  crops  and  in  soils  through  which  water 
percolates  freely,  the  deep  furrow  is  not  to  be  recommended. 
On  the  other  hand,  where  conditions  pertaining  to  water  supply, 
soils,  and  crops  are  favorable,  the  deep  furrow  affords  a  marked 
saving  in  the  water  used  by  checking  evaporation.  This  is 
clearly  brought  out  in  Fig.  59  which  presents  graphically  the 
summarized  results  of  investigations  conducted  at  Reno,  Nevada. 

TABLE  No.  23 

Summary  of  Temperature  of  Air,  Soil,  and  Water,  Humidity,  Wind  Velocity, 

Rainfall,  Free  Water  in  Soil,  and  Losses  from  Free-water  Surface  and 

from  Cultivated  and  Uncultivated  Tanks  of  the  Several  Stations 


.2 

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°F. 

°F. 

°F 

°F. 

P.ct. 

Miles 

In. 

P.ct. 

In. 

In. 

In. 

P.ct- 

Sunnyside,  Wash  .  .  . 

1 

65.2 

71.3 

74.3 

70.9 

0.00 

6.00 

7.25 

1.47 

2.47 

40.3 

Si  Davis,  Cal  

2 

64.5 

75.7 

73.2 

49.8 

9.3 

0.00 

12.85 

9.41 

1.36 

1.91 

28.2 

Reno,  Nev  

2 

56.6 

.... 

67.9 

.... 

58.9 

6.4 

0.39 

8.88 

8.49 

1.09 

1.51 

27.8 

Caldwell,  Idaho 

2 

72  2 

69  2 

69  4 

68  4 

0   14 

6  21 

9  81 

1  91 

2  42 

21  0 

Agricultural  College, 

N.  Mex  

2 

74.5 

.... 

22.7 

8.3 

0.57 



11.13 

1.37 

1.59 

13.8 

Bozeman,  Mont.... 

1 

64.4 

73.9 

74.6 

75.0 

.... 

9.4 

0.99 

17.80 

4.38 

2.30j2.92 

21.2 

Average  

...166.2 

71.572.4 

72.943.8    8.4 

0.35 

10.35 

8.41 

1.58  2.14 

26.4 

30.  The  Duty  of  Water  in  Irrigation. — Duty  of  water  in  irriga- 
tion expresses  the  relation  between  a  given  quantity  of  water  and 
the  area  which  it  serves.  The  water  supply  of  the  arid  region 


WASTE,  MEASUREMENT,  AND  DELIVERY      135 

being  limited  in  volume  means  must  be  taken  to  regulate  its  use. 
My  the  exercise  of  this  control  the  flow  of  streams  is  apportioned 
to  users  of  various  kinds  in  accordance  with  a  pre-determined 
duty.  It  therefore  follows  that  the  duty  of  water  when  fixed  by 
competent  authority  affects  communities  and  enterprises,  as 
well  as  individuals  and  may  affect  states  and  nations. 

All  phases  of  this  subject  vitally  concern  the  irrigator.  He 
wishes  to  secure  for  his  growing  crops  an  adequate  supply  of 
water  at  the  right  time  but  in  its  use  he  may  be  governed  wholly 
or  in  part  by  Federal  statutes,  State  Laws,  State  regulations, 
court  decisions  or  water  right  contracts  which  determine  his 
right  to  divert  and  place  limitations  on  the  quantity  of  water 
which  can  be  used  for  this  purpose.  It  has  therefore  been  con- 
sidered best  to  preface  this  article  with  a  brief  outline  of  the 
broader  aspects  of  the  subject  by  discussing  briefly  the  agencies 
and  methods  employed  to  place  limitations  on  the  quantity  of 
water  which  can  be  used  in  irrigation. 

1.  State  Laws. — The  statutes  of  Idaho  restrict  the  user  to  a 
maximum  quantity  of  1/50  of  a  second-foot  per  acre,  but  the 
courts  of  the  state  are  empowered  to  grant  more  when  necessary. 
This  authority  has  been  abused  in  a  number  of  cases,  since  some 
decrees  have  granted  as  much  as  1  second-foot  for  10  acres. 
In  the  states  of  Wyoming,  Nebraska,  Oklahoma,  New  Mexico  and 
South  Dakota,  the  maximum  limit  is  fixed  by  statute  at  1/70 
of  a  second-foot  per  acre,  while  in  North  Dakota  it  is  1/80  of 
a  second-foot  per  acre.  There  is  a  similar  limitation  in  Nevada 
but  the  unit  adopted  is  in  acre-feet  per  acre,  3  acre-feet  being  the 
maximum. 

To  the  writer  it  seems  unwise  for  any  arid  state  to  fix  limita- 
tions of  this  kind.  Outlined  in  another  part  of  this  article  are 
some  of  the  conditions  which  affect  the  duty  of  irrigation  water. 
These  conditions  not  only  differ  widely  in  different  parts  of  the 
same  state  but  change  from  year  to  year.  The  changes  which 
time  brings  forth  may  be  shown  by  citing  a  few  cases.  Some 
25  years  ago  the  irrigators  of  the  Greeley  district  in  northern 
Colorado  were  using  a  second-foot  of  water  on  40  to  50  acres. 
In  recent  years  the  same  quantity  has  served  fully  three  times  as 
much  land  with  far  better  results  when  measured  in  crop  yields. 
Again  in  the  early  nineties  the  farmers  in  the  Bear  River  Valley 


136  USE  OF  WATER  IN  IRRIGATION 

in  northern  Utah  used  a  second-foot  on  60  to  80  acres  but  during 
the  past  few  years  the  average  duty  has  been  a  second-foot  for 
120  acres.  Furthermore,  when  the  legislative  assembly  of  Wy- 
oming in  1891  limited  the  duty  throughout  that  state  to  1 
second-foot  for  each  70  acres  it  was  actuated  by  the  best  of 
motives.  Such  a  duty  was  then  high.  Now  it  is  too  low  and  the 
state  is  handicapped  by  having  apportioned  so  large  a  volume  of 
its  public  waters  on  the  limit  fixed  by  statute. 

2.  State  Control. — The  control  exercised  by  a  state  may  affect 
the  duty  of  water  in  several  ways.  In  many  of  the  western 
states  the  apportionment,  measurement  and  distribution  of 
the  appropriated  waters  are  in  charge  of  state  officers,  who 
are  required  to  distribute  the  flow  of  streams  in  accordance 
with  adjudicated  rights.  It  often  happens  that  by  the  exercise 
of  good  judgment  in  the  performance  of  this  duty  they  can  modify 
the  defects  or  temper  the  harshness  of  court  decisions.  Some- 
times the  transfer  of  a  little  water  for  a  short  time  from  a  superior 
to  an  inferior  right  may  save  a  farmer's  crops  without  inflicting 
any  injury  on  his  more  fortunate  neighbor  who  has  a  prior  right. 
Such  officers  can  be  of  so  great  service  to  the  state  in  maintaining 
friendly  relations  among  irrigators,  in  the  prevention  of  waste 
of  water,  in  the  wise  use  of  seepage  and  return  waters,  and  in 
securing  the  largest  possible  benefits  from  all  available  sources  of 
supply,  that  the  trend  of  public  opinion  favors  giving  them  large 
discretionary  powers  in  the  exercise  of  their  public  duties. 

Another  form  of  state  control  is  exercised  by  state  land 
boards  in  examining  and  approving  the  duty  of  water  on  lands 
under  Carey  Act  projects.  In  Idaho,  for  example,  the  prevailing 
duty  under  such  projects  is  1  second-foot  of  water  for  each 
80  acres  of  land,  delivered  at  the  head  of  the  farmer's  laterals. 

State  control  is  likewise  exercised  through  special  tribunals 
or  water  courts.  In  Wyoming  the  special  tribunal  is  called  the 
Board  of  Control  and  it  is  justly  entitled  to  the  highest  praise 
for  its  efficiency.  From  the  time  this  Board  was  created  in  1890 
and  organized  in  1891,  up  to  January  1,  1914,  it  had  adjudicated 
12,500  rights  to  the  use  of  water.  These  rights  serve  1,510,000 
acres.  Considering  the  small  number  of  its  decisions  that  have 
been  appealed  no  other  court  can  show  so  good  a  record. 

The  writer  is  in  favor  of  a  special  tribunal  with  state-wide 


WASTE,  MEASUREMENT,  AND  DELIVERY      137 

jurisdiction  for  the  determination  of  water  rights.  He  is  likewise 
in  favor  of  handing  over  to  competent  state  officers  the  regulation 
of  the  water  supply.  Acting  in  accordance  with  these  views, 
Mr.  H.  W.  Grunsky  and  the  writer,  when  called  upon  to  advise 
the  ministry  of  British  Columbia  on  matters  pertaining  to  irriga- 
tion, recommended,  among  other  things,  a  form  of  water  license 
for  the  Province.  This  form  of  final  license  is  in  force  at  this 
writing  and  contains  the  following  "terms  and  conditions": 
(a)  source  of  supply,  (b)  point  of  diversion,  (c)  the  date  from  which 
the  license  shall  take  precedence,  (d)  the  purpose  for  which  the 
water  is  to  be  used,  (e)  the  maximum  quantity  of  water  which 
may  be  used  until  lawfully  altered,  and  the  maximum  quantity 
of  water  per  annum  which  may  be  used  on  each  acre  actually 
irrigated  in  acre-feet,  (f)  the  period  of  the  year  during  which 
the  water  may  be  used,  (g)  the  area  and  description  of  the  land 
to  which  the  water  is  appurtenant,  (h)  a  concise  description  of 
the  works,  (i)  a  limitation  of  the  water  used  per  acre  to  that 
quantity  which  experience  may  hereafter  determine  to  be  neces- 
sary for  the  production  of  crops  in  the  exercise  of  good  husbandry, 
and  (j)  a  reservation  to  the  Province  of  the  right  to  distribute 
water  in  rotation  of  time  or  otherwise  for  the  purpose  of  securing 
the  most  economical  use  of  water. 

Some  may  regard  these  terms  and  conditions  as  unduly  rigid 
and  unfair  to  the  irrigator.  On  the  other  hand,  the  belief  is 
becoming  quite  general  that  the  high  value  and  scarcity  of  water 
and  the  demand  which  is  being  made  on  this  natural  resource  will 
soon  force  the  abandonment  of  lax  laws  and  wasteful  use  affecting 
it. 

3.  Court  Decisions. — Of  the  adjudicated  rights,  by  far  the 
largest  number  have  been  determined  by  district  courts.  Mem- 
bers of  the  legal  profession  generally  favor  this  mode  of  procedure; 
and  no  valid  objection  can  be  raised  to  it,  if  only  questions  of 
law  are  involved.  Needless  to  state,  however,  the  proper  de- 
termination of  a  right  to  the  use  of  water  resembles  that  of  the 
survey  and  location  of  a  piece  of  land.  It  is  based  on  the  re- 
sults of  investigations  pertaining  to  water  and  land  measure- 
ments, the  carrying  capacities  of  ditches,  seepage  and  return 
wators,  character  of  the  soil,  water  requirements  of  crops  and 
other  physical  facts  of  like  nature.  Considering  the  question 


138  USE  OF  WATER  IN  IRRIGATION 

from  this  point  of  view  it  may  well  be  doubted  whether  the 
ordinary  law  court  is  the  best  tribunal  for  such  a  purpose.  In 
any  event,  grave  mistakes  have  been  made  by  such  courts  in  the 
past.  Some  20  years  ago  a  part  of  the  public  waters  of 
Colorado  were  adjudicated  in  a  haphazard  way  with  little  or  no 
effort  to  ascertain  the  physical  facts.  Many  adjudications  were 
based  on  the  cross-sectional  area  of  the  ditch  or  canal  without 
reference  to  its  grade  or  the  velocity  of  flow.  In  one  case  33 
second-feet  of  water  were  granted  to  120  acres  of  land,  and  in 
another  31  second-feet  to  200  acres.  The  owner  of  the  ranch 
last  referred  to  was  recently  offered  $100,000  for  the  land 
and  the  water  right,  the  latter  being  appraised  at  about 
$60,000. 

It  is  but  just  to  state  that  these  decisions  were  rendered  at 
a  time  when  water  possessed  less  value  than  it  does  today.  Re- 
cent water  decisions  of  the  district  courts  are  based  on  more 
accurate  data,  yet  the  tendency  is  still  in  the  direction  of  grant- 
ing a  generous  allowance,  disregarding  the  public  welfare  and 
allowing  too  much  latitude  as  to  the  period  of  time  when  the 
water  can  be  used.  Some  of  these  weak  features  are  brought 
out  in  the  following  references: 

In  1909  the  rights  to  the  use  of  water  on  the  West  Gallatin 
valley  in  Montana  were  determined  by  a  decree  of  the  court. 
In  this  suit,  144  canals,  providing  water  for  83,600  acres  of  land, 
were  involved.  In  arriving  at  a  decision  some  attempt  at  a 
rough  classification  of  soils  was  made  for  the  purpose  of  adjusting 
the  amount  of  water  decreed  to  the  needs  of  the  soil.  In  general, 
1  miner's  inch  per  acre  (1/40  second-foot)  was  decreed  to  the 
more  porous  soils  and  3/4  miner's  inch  to  the  silt  and  clay 
loams.  These  quantities  were  supplemented  by  allowances 
for  seepage  losses  in  the  ditches  and  canals.  These  losses  varied 
from  less  than  1  per  cent,  to  5  per  cent,  per  mile.  While 
the  case  was  pending  competent  parties  ascertained  for  the 
court  the  proper  duty  of  water  for  both  classes  of  soil.  These 
were  based  on  a  24-hour  use  of  the  water  in  each  day.  The 
judge,  however,  did  not  think  it  right  to  compel  users  to  irrigate 
during  the  night  and  so  based  the  decree  on  a  12-hour  day  by 
granting  double  the  quantity  of  water  required  per  acre.  In  this 
decision  the  seasonal  time  of  use  is  not  defined  and  in  consequence 


WASTE,  MEASUREMENT,  AND  DELIVERY      139 

no  provision  is  made  for  appropriating  water  from  the  same 
stream  for  storage  or  other  purposes. 

In  a  decision  rendered  in  1910  by  Judge  Kent  of  Arizona,  the 
standard  duty  of  water  was  fixed  for  much  of  the  irrigated  land 
in  the  Salt  River  Valley.  The  area  affected  by  the  decree  em- 
braced 179,970  acres  and  a  constant  flow  of  48  miner's  inches 
was  allowed  to  each  quarter  section  of  land  measured  and  de- 
livered at  the  land.  This  is  equivalent  to  1  second-foot  to 
each  133  1/3  acres  or  5.42  acre-feet  per  acre  per  annum.  A 
standard  transmission  loss  due  to  seepage  and  evaporation  was 
also  adopted.  This  loss  was  placed  at  1  per  cent,  of  the  flow 
per  mile  of  main  canal.  Although  of  recent  date,  this  decree  has 
a  far-reaching  influence  in  that  it  has  fixed  for  the  past  3 
years  the  duty  of  water  for  more  than  one-half  of  the  irrigated 
lands  of  Arizona. 

A  peculiar  feature  of  the  decree  is  that  the  court  retained 
jurisdiction  of  the  case  and  the  issues  raised  in  the  suit  with  a 
view  to  modifying  any  portion  later.  This  reservation  has 
great  significance  when  applied  to  duty  of  water  and  seems  to 
be  the  recognition  of  the  fact  that  the  water  requirements  of 
crops  and  soils  change  as  conditions  change.  While  a  decision 
of  this  kind  is  quite  arbitrary  in  character  so  long  as  it  is  in  effect, 
yet  the  opportunity  which  it  affords  for  modification  encourages 
the  fullest  investigation  of  the  amount  of  water  actually  required 
for  different  crops  and  soils.  The  results  of  investigations  thus 
far  made  by  the  Office  of  Experiment  Stations,  U.  S.  Depart- 
ment of  Agriculture,  under  the  direction  of  P.  E.  Fuller,  seem  to 
point  to  the  conclusion  that  3  acre-feet  per  acre  when 
economically  applied  will  suffice  for  average  crops  and  soils.  If 
further  investigation  should  confirm  this  view,  it  would  justify 
an  early  modification  of  the  present  duty  of  water  in  the  Salt 
River  Valley. 

4.  Water  Right  Contracts. — In  general  it  may  be  stated  that 
court  decisions  in  allotting  water  supplies  favor  the  water  users 
at  the  expense  of  the  public  while  water  right  contracts  favor 
the  company  at  the  expense  of  the  water  user.  Whether  justly 
or  unjustly,  water  right  contracts  likewise  exert  a  potent  influence 
in  restricting  the  quantity  of  water  used  in  irrigation.  While 
many  companies  and  enterprises  live  up  to  their  agreements, 


140  USE  OF  WATER  IN  IRRIGATION 

some  delivering  to  consumers  more  water  than  the  contracts 
called  for,  others,  through  stress  of  circumstances,  seek  to  over- 
come the  defects  of  a  short  water  supply  or  unsafe  structures, 
or  both,  by  the  insertion  of  one-sided  agreements  in  the  con- 
tracts. Most  contracts  of  this  kind  stipulate  that  the  com- 
pany agrees  to  furnish  a  fixed  quantity  of  water  which  must  be 
used  on  a  definite  area;  and  in  case  of  water  shortage  at  any  time 
the  amount  available  is  to  be  prorated.  Such  provisions,  when 
robbed  of  their  legal  phraseology,  mean,  as  R.  P.  Teele  of  the 
U.  S.  Department  of  Agriculture  states  (Annual  Report,  O.  E. 
S.,  1908)  "That  the  farmer  takes  what  water  he  can  get,  for 
which  he  shall  pay  a  flat  rate  per  acre  regardless  of  the  quantity 
received." 

Duty  of  water  under  contracts  is  expressed  in  various  ways 
but  measured  in  total  volume  for  any  one  season  it  is  seldom 
less  than  1  acre-foot  or  more  than  3  acre-feet  per  acre. 

UNITS  OF  MEASUREMENT. — The  manner  in  which  duty  of 
water  is  expressed  differs  throughout  the  irrigated  region.  The 
unit  of  water  may  be  the  acre-foot,  the  second-foot,  the  miner's 
inch,  or  the  U.  S.  Gallon  per  minute.  In  the  rice  belt  where  much 
of  the  water  is  pumped,  duty  is  usually  expressed  in  gallons  per 
acre.  Again,  since  the  natural  precipitation  is  measured  in 
depth  over  the  surface  and  is  a  factor  to  be  reckoned  with  in 
connection  with  canal  duty,  the  custom  of  using  either  the  acre- 
foot  or  the  acre-inch  per  acre  to  express  duty  has  become  quite 
general.  In  the  more  arid  states  where  large  quantities  of  ditch 
water  are  required  the  acre-foot  is  the  better  term,  but  in  the 
humid  region  where  small  quantities  are  used  as  a  supplemental 
supply  during  periods  of  droughts,  the  acre-inch  is  preferable. 
Another  custom  deserving  of  some  recognition  allows  a  certain 
quantity  of  water  per  month  delivered  as  required  rather  than 
per  season.  The  necessity  for  corporations  and  irrigation 
enterprises  of  all  kinds  obligating  themselves  to  do  this  is  shown 
by  the  monthly  water  requirements  of  the  crops  in  Table  24. 

PLACE  OF  MEASUREMENT. — The  duty  of  water  may  be  meas- 
ured (1)  at  the  intake  of  the  main  canal,  (2)  at  the  intake  of  the 
lateral,  or  (3)  at  the  margin  of  the  farm.  The  results  of  meas- 
urements made  at  the  first-named  place  are  often  spoken  of 
as  the  gross  duty,  since  they  include  all  transmission  losses 


WASTE,  MEASUREMENT,  AND  DELIVERY      141 

(Art.  26).  Those  obtained  at  the  margins  of  fields  are  fre- 
quently designated  the  net  duty,  since  all  losses  in  transit  are 
excluded. 

CONDITIONS  AFFECTING  DUTY. — It  has  long  been  recognized 
that  the  amount  of  water  required  in  irrigation  differs  widely  on 
adjacent  farms  and  in  different  localities  and  states.  In  briefly 
considering  the  causes  of  this  the  writer  will  not  attempt  to 
name  all  the  conditions  nor  to  designate  the  order  in  which  they 
shall  be  presented. 

(1)  Value  of  Water. — Where   water   is   plentiful   and   cheap 
less  care  is  certain  to  be  taken  in  its  use  and  less  money  ex- 
pended in  facilities  for  its  conveyance  and   application.     This 
accounts  for  the  large  amount  of  water  per  acre  which  is  used 
in  parts  of  central  California  and  the  relatively  small  amounts 
used  in  southern  California.     There  are,  of  course,   exceptions 
to  this  rule.     In  Florida,  for  example,  water  is  both  abundant 
and  cheap  but  irrigation  water  is  exceptionally  high  on  account 
of  the  methods  employed  in  its  distribution  and  application,  the 
cost  of  which  varies  from  $50  to  $250  per  acre. 

(2)  Character  of  Soil  and  Subsoil. — Porous  soils,  on  account 
of  the  losses  due  to  deep  percolation,  require  much  more  water 
than  retentive  soils.     This  is  illustrated  in  a  marked  degree  by 
the  use  of  water  on  the  Reclamation  Service  project  at  Umatilla, 
Oregon.     On  the  "  sand  hill "  area  north  of  the  town  of  Hermiston 
in  particular,  the  soil  contains  60  to  90  per  cent,  of  coarse  sand 
and  gravel  with  little  fine  sand  and  an  almost  negligible  amount 
of  silt  and  clay.     The  irrigation  season  extends  from  March 
16   to  October  16 — 210  days — during  which  period  contracts 
call  for  the  delivery  to  the  land  of  2.8  acre-feet  of  water  per 
acre.     In  1912  the  actual  average  delivery  to  the  entire  pro- 
ject was  9.7  acre-feet  per  acre.     On  the  more  porous  portions 
it  is  considered  necessary  to  irrigate  alfalfa  three  or  four  times 
for  each  cutting.     One  grower  with  7  acres  irrigated  five  times 
for  the  first  crop,   and    six    times  for  each   of  the    following 
three  cuttings,  making  23  irrigations  for  the  season. 

.(3)  Climate. — The  rain  which  falls  during  the  crop-growing 
season  and  to  a  less  extent  the  annual  precipitation,  have  a 
marked  effect  on  crop  production  and  the  use  of  irrigation  water. 
In  one  sense  all  irrigation  water  is  supplementary  and  the  more 


142  USE  OF  WATER  IN  IRRIGATION 

rain  which  is  absorbed  by  the  soil,  the  less  is  the  need  for  ar- 
tificial supplies.  It  is  likewise  true  that  much  of  the  rain  which 
falls  during  the  period  of  growth  is  wasted.  The  light  shower 
may  invigorate  certain  crops  but  it  seldom  adds  anything  to 
the  moisture  content  of  the  soil,  being  too  soon  dissipated 
in  vapor.  It  may  actually  deprive  the  soil  of  moisture  by  break- 
ing down  the  dust  mulch.  Not  only  rainfall  but  temperature, 
the  prevalence  of  high,  warm  winds,  the  rate  of  evaporation,  and 
other  climatic  factors  exert  an  influence  on  duty  of  water.  The 
traveler  in  proceeding  north  from  Arizona  and  New  Mexico  into 
the  Province  of  British  Columbia  can  not  but  observe  the  heavy 
growth  of  timber  which  a  light  rainfall  supports  in  the  south- 
central  part  of  this  Province.  On  account  of  the  heavy  evapora- 
tion in  the  southwestern  states,  the  same  rainfall  there  pro- 
duces only  desert  plants. 

(4)  Proper   Channels  and  Structures. — In   discussing  the   ef- 
ficiency of  irrigation  water  in  Art.  25  the  extent  of  the  losses 
due  to  conducting  water  from  place  to  place  was  pointed  out. 
Until  this  waste  is  much  reduced  a  high  duty  of  water  can  not 
be  secured,     Furthermore,    since  the   small   ditches   made   by 
the  farmer  waste  a  higher  percentage  of  water  there  is  much 
need  for  reducing  this  loss  by  careful  and  efficient  construction 
and  in  some  cases  even  to  the  extent  of  making  them  water- 
tight.    Much  needless  waste  can  likewise  be  saved  by  making 
shorter  runs. 

(5)  Preparation    of   Land. — Coupled    with    proper    facilities 
for  the  carriage  and  distribution  of  the  head  used  there  is  also 
required  the  careful  preparation  of  each  field.     To  attempt  to 
irrigate  land  which  has  a  rough,  uneven  surface,  is  frequently 
the  cause  of  much  waste  of  water,  extra  labor,  small  yields  and 
eventually    damaged    land.     Not    only   thorough    grading   but 
thorough  cultivation  are  essential. 

(6)  Diversified    Farming. — Cereals     usually     require     to     be 
watered  one  or  more  times  during  the  period  from  the  time  the 
plants  cover  the  ground  until  the  grain  is  well  " headed  out." 
This  represents  a  short  period  and  the  farmer  who  raises  only 
grain  has  no  further  use  of  irrigation  water  for  the  balance  of 
that  season.     On  the  other  hand,  in  rotating  grain  with  such 
crops  as  alfalfa,  roots  and  fruit,  these  latter  require  late  water 


WASTE,   MEASUREMENT,  AND  DELIVERY      143 

and  the  use  of  the  same  flow  is  thus  extended  over  a  longer 
period  and  in  consequence  waters  a  larger  acreage. 

(7)  Time    and  Manner  of   Water   Delivery. — Water,    as   well 
as  labor  and  time  can  be  saved  and  an  economical  duty  secured 
where   conditions   are  favorable    by   using  large  quantities  of 
water  for  short   periods  of  time.     Irrigators  in  the  northern 
tier  of  states  have  been  slow  to  abandon  the  continyal  use  of 
small  heads.     While  this  method  has  its  advantages  for  the  man 
having  a  large  farm  and   crude  irrigation  appliances,   it  will 
be  found  profitable  on  the  whole  to  rotate  the  supply  with 
one's  neighbors.     Watering  crops  is  too  important  to  be  treated 
as  a  side  issue.     If  one  attempts  to  attend  to  other  duties  while 
water  is  running  on  his  fields,  only  visiting  the  latter  at  long 
intervals,  small  yields  are  likely  to  result.     It  is  better  to  see 
that  the  water  is  well  distributed  while  it  can  be  used.     When 
the  time  of  use  has  expired  the  headgate  is  closed  and  the  water 
flows  on  to  the  neighboring  farm. 

(8)  Kind  of  Crops. — The  kind  of  crop,   whether  cultivated 
or  uncultivated,  and  the  length  of  season  that  it  needs  water, 
have  a  direct  bearing  on  the  amount  of  water  required.     Winter 
grains  seem  to  require  the  least  irrigation  water  because  they 
mature  early  and  are  able  to  make  good  use  of  the  winter  pre- 
cipitation.    Spring  grains  are  not  usually  planted  until  some  of 
the  winter  precipitation  has  been  evaporated.     Cultivated  crops, 
because  of  the  moisture  that  can  be  saved  by  cultivation  (Art. 
29)  require  less  water  than  uncultivated  crops.     Alfalfa,  hay 
and  pasture  grasses  grow  luxuriantly  through  a  long  season  and 
thus  require  the  most  water,  it  being  found  that  such  crops 
require  about  twice  as  much  as  grains. 

(9)  Fertility  of  the  Soil. — Arid  soils  are  deficient  in  vegetable 
matter  and  when  this  want  is  supplied  by  the  right  kind  of 
rotation  and  by  good  farming  generally,  the  soil  becomes  more 
retentive  of  moisture  and  a  unit  of  water  will  supply  a  larger 
area  than  is  possible  when  the  soil  is  in  a  raw  state.     What 
is  true  of  humus  and  nitrogen  is  also  true  of  other  fertilizers. 
Generally  speaking,  the  richer  the  soil  and  the  better  it  is  tilled, 
the  less  the  water  requirements  for  any  one  crop. 

(10)  Manner  of  Paying  for  Water. — Paying  for  water  by  the 
season  on  an  acreage  basis  tends  to  lower  the  efficiency  of  water. 


144  USE  OF  WATER  IN  IRRIGATION 

As  has  been  pointed  out  elsewhere  the  water  user  under  such 
a  contract  is  given  no  chance  to  reduce  his  water  bill  by  the 
exercise  of  economy.  On  the  other  hand,  the  practice  of  pay- 
ing only  for  what  water  one  receives  is  invariably  followed  by 
an  economical  use. 

(11)  Method  of  Applying   Water. — Faulty  methods  of  appli- 
cation are,  liable  to  cause  large  losses  in  deep  percolation,  evapora- 
tion, run-off  or  in  any  or  all  of  these  combined. 

(12)  Legal  Restrictions. — The  effect  of  these  on  duty  of  water 
have  already  been  considered  in  discussing  the  limitations  im- 
posed by  statutory,  regulatory  and  judicial  means. 

INVESTIGATING  DUTY  OF  WATER. — A  knowledge  of  the  service 
or  duty  which  water  performs  is  necessary  in  all  irrigated  regions. 
This  fact  was  early  recognized  in  the  development  of  the  arid 
West.  In  1892  the  Colorado  Experiment  Station  published  a 
bulletin  on  this  subject  which  gave  the  results  of  investigations 
made  by  Professor  Carpenter.  Two  years  later  the  writer  be- 
gan similar  investigations.  It  was  not,  however,  until  Congress 
in  1898  appropriated  money  for  irrigation  investigations  that 
a  study  of  duty  of  water  became  general  throughout  the  West. 
An  urgent  demand  existed  at  that  time  for  more  information  con- 
cerning the  quantities  of  water  used  and  required  in  irrigation. 
This  information  was  needed  by  courts  in  determining  water 
rights,  by  state  officers  in  apportioning  water  supplies,  by  en- 
gineers in  planning  the  capacities  of  canals  and  in  estimating  the 
areas  of  land  which  they  would  serve,  by  the  managers  of  canal 
companies  in  drawing  up  water  right  contracts,  and  by  those  who 
used  the  water  on  their  farms.  Studies  of  this  kind  were  con- 
tinued for  several  years  and  the  collected  data  proved  of  lasting 
benefit  since  they  resulted  in  the  framing  of  wise  legislation  and 
in  the  adoption  of  sound  public  policies  in  relation  to  water 
during  a  formative  stage  of  irrigation  development  in  this 
country.  True,  the  results  obtained  have  been  criticised  by 
agriculturists  and  others  who  contend  that  too  little  attention 
was  paid  to  the  character  of  the  soil  and  subsoil  and  to  the  kind 
of  crops  grown.  Such  critics  overlooked  the  fact  that  the  in- 
vestigations as  first  planned  were  intended  to  supply  informa- 
tion regarding  the  legal,  administrative  and  engineering  features 
of  irrigation  rather  than  the  agricultural.  Besides,  the  funds 


WASTE,  MEASUREMENT,  AND  DELIVERY      145 

available  were  too  small  to  permit  a  thorough  study  of  the  sub- 
ject in  all  its  phases.  At  that  time  it  was  infinitely  better 
to  ascertain  the  general  average  duty  over  100,000  acres  than 
to  spend  the  same  amount  of  money  in  more  detailed  studies  on  a 
40-acre  tract. 

Both  land  and  water  measurements  were  made  by  men 
familiar  with  this  class  of  work.  The  weir  and  rating  flume 
were  the  most  commonly  used  devices  for  measuring  water.  To 
secure  a  continuous  record  of  flow,  recording  registers  were 
imported  from  France  until  the  demand  for  such  instruments  was 
pressing  enough  to  induce  American  firms  to  make  them.  At 
first  the  work  was  quite  generally  confined  to  making  a  con- 
tinuous measurement  of  the  quantities  of  water  which  flowed 
through  the  intakes  of  the  main  canals  but  later  the  flow  through 
laterals  and  farmers'  ditches  was  measured.  These  measure- 
ments indicated  a  large  transmission  loss  which  took  place  be- 
tween the  main  intake  and  the  farmer's  headgates,  and  efforts 
were  made  to  ascertain  the  extent  of  these  losses. 

The  writer  was  one  of  the  first  to  apply  different  quantities 
of  water  to  experimental  plats  in  order  to  determine  the  effect 
of  water  on  crop' production.  This  work  is  still  carried  on  in 
various  parts  of  the  West  and  bids  fair  to  throw  considerable 
light  on  the  proper  amount  of  water  to  apply  to  the  different 
crops. 

A  plan  of  investigation  which  combined  the  plat  and  the 
large  area  was  devised  by  Don  H.  Bark,  irrigation  engineer 
in  charge  of  irrigation  investigations  in  Idaho.  Mr.  Bark's 
plan  consists  in  dividing  a  typical  cropped  field  into  three 
parts.  The  owner  applies  to  one  part  in  one  or  more  irrigations 
that  quantity  of  water  which  in  his  judgment,  will  produce  the 
largest  yield.  Mr.  Bark's  assistant  applies  by  the  same  method  a 
larger  amount  to  the  second  and  a  smaller  amount  to  the  third 
part.  By  means  of  weirs  the  amount  of  water  applied  as  well 
as  the  run-off  is  carefully  measured.  The  yield  on  each  sub- 
division is  determined  at  harvest  time  and  by  comparing  the 
quantity  of  water  applied  with  the  yield,  a  fairly  accurate  con- 
clusion may  be  drawn  as  to  the  proper  duty  of  water  for  that 
soil  and  crop.  A  large  number  of  such  experiments  have  been 
financed  in  southern  Idaho  by  funds  obtained  from  the  State 
10 


146 


USE  OF  WATER  IN  IRRIGATION 


Land  Board  and  the  Office  of  Experiment  Stations,  U.  S. 
Department  of  Agriculture  and  the  results,  which  are  summarized 
below,  possess  great  value,  not  only  to  that  state  but  to  the 
West  in  general. 

RESULTS  OF  INVESTIGATIONS. — The  following  table  gives  the 
average  results  obtained  during  the  years  1910,  1911,  and  1912 
throughout  southern  Idaho.  It  shows  that  a  project  devoting 
about  half  its  area  to  grain  and  other  crops  which  require  the 
least  water,  and  the  "other  half  to  alfalfa,  clover  and  pasture, 
which  need  the  most  water,  will  require  on  an  average  about 
2  acre-feet  delivered  to  each  acre  exclusive  of  precipitation, 
which  varied  from  2  to  6  inches.  Of  this  amount  0.82  per 
cent,  was  required  in  April,  16.08  per  cent,  in  May,  31. 67  per 
cent,  in  June,  32.25  per  cent,  in  July,  16.38  per  cent,  in  August 
and  2.79  per  cent,  in  September. 

TABLE  No.  24 

Summary  of  Depths  of  Water  applied  by  Months  to  168  Fields  of  Grain 

and  Alfalfa  on  Medium  Clay  and  Sandy  Loam  Soils  in  Idaho,  Altitudes 

ranging  from  2400  to  5000  Feet,  Seasons  1910,  1911,  1912 


Crop 

a 

No. 
of 
plots 

April 

May, 
feet 

June, 
feet 

July, 
feet 

Aug., 
feet 

September 

Total 
for 
sea- 
son, 
feet 

1-15 

feet 

16-30 
feet 

1-15 
feet 

16-30 

feet 

Grain 

1910 
1910 
1911 
1911 
1912 
1912 

39 

17 
49 
18 
34 
11 

0.320 
0.531 
0.021 
0.525 

0.6453 
0.7200 
0.7170 
0.3080 
0.9140 
0  .  4430 

0.6245 
31.67 

0.495 
0.602 
0.428 
0.945 
0.650 
0.697 

0.636 
32.25 

0  .  0954 
0.5510 
0  .  0060 
0.7500 
0.0590 
0.4740 

0.323 
16.38 

0.0636 
0.1990 

0.031 

1.556 
2.540 
1.172 
2.7813 
1.623 
2.160 

1.972 
100.00 

Alfalfa     .  . 

0.053 

0.018 

Alfalfa  
Grain  
Alfalfa  

0.025 

0.009 
0.46 

0.007 
0.36 

0.508 
0.318 

16.08 

0.0376 
0.050 

2.54 

0.005 
0.25 

Percentage 
of  total.  .  .  . 

Some  results  of  duty  of  water  under  typical  canals  throughout 
the  arid  regions  are  given  in  Table  25. 

Similar  results  of  duty  of  water  under  diversions  from  streams 
are  given  in  Table  26. 

WATER  REQUIREMENT  OF  CROPS. — The  quantity  of  water  re- 
quired for  various  crops  under  field  conditions  has  been  treated 
in  Arts.  35  to  36.  The  specific  cases  of  water  duty  therein  cited 


\\'.\XTE,  MEASUREMENT,  AND  DELIVERY      147 
TABLE  No.  25 


Name  of  canal 

Location 

Class  of 
soil 

Season 

Length  of 
season 

No.  of 
acres 

Duty, 
ac. 
ft. 
per 
ar. 

Riverside  
Farmer's  Coop  
Farmer's  Union  
Settlers  

Boise  Valley, 
Idaho. 
Boise  Valley, 
Idaho. 
Boise  Valley, 
Idaho. 
Boise  Valley, 

Clay  loam 
Clay  loam 
Clay  loam 
Clay  loam 

1911-12 
1911-12 
1911-12 
1911-12 

Apr.  1-Oct.  31 
Apr.  1-Oct.  31 
Apr.  1-Oct.  31 
Apr  1-Oct  31 

3,004 
7,160 
6,993 
6,440 

8.31 
5.13 
5.60 
2  95 

Boise  Valley  

Idaho. 
Boise  Valley, 

Gravelly 

1911-12 

Apr  1-Oct.  31 

751 

3  15 

Eureka  No.  1  

Idaho. 
Boise  Valley, 

Gravelly 

1911-12 

Apr  1-Oct.  31 

2  174 

2  51 

Pioneer  
Randall 

Idaho. 
Boise  Valley, 
Idaho. 
Rigby,  Idaho 

Gravelly 
Gravelly 

1911-12 
1912 

Apr.  1-Oct.  31 
Apr  1-Oct  31 

1,137 
3  255 

5.72 
6  87 

Clark  and  Edwards.  . 

Rigby,  Idaho 
Boise  Valley, 

Gravelly 
Clay  loam 

1912 
1906-12 

Apr.  1-Oct.  31 
Apr  1-Oct  31 

1,362 
25  710 

10.04 
4  15 

U.    S.    R.   S.   upper 
system. 
So.  Side  Twin  Falls 

St   John     

Idaho. 
Boise  Valley, 
Idaho. 
Twin  Falls, 
Idaho. 
Malad,  Idaho 

Clay  loam 
Clay  loam 
Clay  loam 

1912 
1910-12 
1913 

Apr.  16- 
Oct.  31 
Apr.  1-Oct.  31 

Apr  25- 

45,664 
147,309 
1  518 

2.88 
4.90 
1  91 

Larimer  &  Weld  

Cache     la     Poudre, 
No.  2. 
Loveland  &  Greeley 

Colorado  

N.  Ft.  Collins, 
Colo. 
Greeley,  Colo. 

Loveland- 
Greeley,  Colo. 
Arkansas  Val. 

Clay  loam 
Clay  loam 
Sandy  loam 

1910-12 
1910-12 
1910-12 
1912 

Sept.  15 
May  3-Oct.  24 

Apr.  2  1-Oct.  3 
Apr.  7-Nov.  14 

51,666 
39,300 
19,330 
52,850 

1.49 
1.61 
1.11 
1   61 

1912 

31  870 

3  02 

Logan-Hyde      Park 

Logan    Utah 

1909 

3  183 

5  42 

&  Smithfield. 
Logan  &  Richmond 

Logan   Utah 

1909 

Sept.  10 
May  25- 

3  375 

5   16 

Logan  &  Benson.  .  .  . 

Logan    Utah 

1909 

Aug.  31 
June  13- 

'5  467 

1   14 

Bothwell     or     Bear 

Garland,  Utah 

1902-05 

Aug.  31 
Apr  1- 

34  778 

3  85 

River. 
East  Jordan 

So     Salt   Lake 

1904  08 

Sept.  30 
May  1 

16  000 

1  96 

Grand  Valley 

Utah. 
Grand  Jc 

-12 
1909-11 

Oct.  1 
Apr  1-Oct  31 

40  000 

3  50 

Wyo.    Development 
Co. 
Riverside  Water  Co. 

Colo. 
Wheatland, 
Wyo. 
Riverside,  Cal. 

Clay  loam 

1912 
1899-05 

May  1- 
Sept.  30 

33,500 
80  667 

2.93 
2  25 

Imperial  Water  Co. 

Imperial      Val- 

1905 

120  000 

2  04 

Xos.  1.  4.  :>,  ami  7. 

ley,  Cal. 

148 


USE  OF  WATER  IN  IRRIGATION 


TABLE  No.  26 
Gross  Duty  of  Water,  by  Streams 


Stream 

Canal 

Approxi- 
mate area 
irrigated 

Water 
diverted 
per  acre 

Arizona:  Salt  River.  .  .  . 
California  : 
.  Santa  Ana  
Santa  Clara  

Average  of  several  

Gage  
Average  of  several  

Acres 
113,000 

7,000 
5,160 

Acre-feet 
3.42 

2.16 
2.00 

Tule  
Tuolumne. 

Average  of  several  
Modesto  ... 

5,000 
7,000 

4.94 
13  18 

Tuolumne 

Turlock 

20000 

8  34 

Cache  Creek  

Moore  

7,000 

3.15 

Colorado  : 
Arkansas 

Amity 

16,000 

4  92 

Arkansas  

Lake  

15,000 

2.58 

Grand              .  .    .  . 

Grand  Valley.  .  .  . 

22,000 

4  11 

Cache  la  Poudre.  . 

New  Cache  la  Poudre  

.  30,000 

2.21 

Big  Thompson  .... 
St.  Vrain     

Average  of  two  
Supply  

32,000 
7,000 

1.80 
1  79 

Clear  Creek  

Average  of  three  

53,000 

1.37 

South  Platte  
Montana  : 
Gallatin  
Yellowstone 

Average  of  several  

Average  of  several  
Big  Ditch 

67,000 

8,000 
25  000 

2.90 

3.55 
2  71 

Bitterroot  

Average  of  several. 

20,000 

4  69 

Nevada:  Truckee 

Orr  Ditch  .  . 

6,000 

7  08 

Nebraska  : 
North  Platte...... 
New  Mexico  :  Pecos  .  . 

Average  of  several  
Pecos  

80,000 
8,500 

4.00 
7.90 

Utah: 
Big  Cottonwood.  .  . 
Logan  

Average  of  several  
Average  of  two  

8,000 
6,000 

4.13 
4.08 

Bear  River 

Bear  River 

17,000 

4  84 

Washington  : 
Naches  
Yakima  

Average  of  several  
Average  of  several 

15,000 
50,000 

4.86 
5.70 

Wyoming  : 
Laramie  
Deer  Creek  
Horseshoe  

Canal  No.  2  
Average  of  several  
Average  of  several  

6,500 

3.72 
10.40 
9.75 

may  be  regarded  as  typical  for  various  crops  under  economic 
use.  These  figures  do  not,  however,  represent  the  actual  water 
requirement  for  each  crop  since  more  or  less  water  is  wasted  in 


PLATE  VII 


PLATE  VII 


a 

o> 

d 


.2* 

.      O" 

d " 

S  o 

o3 

pq 


WASTE,  MEASUREMENT,  AND  DELIVERY      149 

applying  it  to  fields.  Investigators  have  attempted  to  eliminate 
this  waste  by  growing  plants  in  vessels  and  the  results  of  their 
investigations  are  briefly  summarized  in  the  following  table  which 
is  compiled  in  part  from  Buls.  284  and  285  by  Briggs  and 
Shantz  of  the  Bureau  of  Plant  Industry,  U.  S.  Department  of 
Agriculture. 

In  scanning  the  figurles  which  represent  in  the  table  the  ratio 
in  pounds  between  the  water  absorbed  and  a  pound  of  air-dried 
crop  produced,  one  can  not  but  note  their  incongruity.  In 
many  respects  they  do  not  seem  to  agree  with  the  views  of  prac- 
tical growers.  Rye,  for  example,  which  requires  little  moisture 
according  to  the  belief  of  many  farmers,  stands  near  the  head 
of  the  list,  the  ratio  averaging  724  in  the  experiments  conducted 
at  Akron,  Colorado.  Again,  the  average  of  experiments  on  red 
clover  made  in  England,  Germany  and  the  State  of  Wisconsin 
is  354  pounds  of  water  to  a  pound  of  dried  clover  hay.  Judging 
from  these  results  the  water  requirement  of  rye  is  more  than 
double  that  of  red  clover. 

While  the  results  which  have  been  assembled  in  the  table  can 
not  be  accepted  as  a  safe  guide  to  practise,  yet  they  show  that  a 
beginning  has  been  made  in  this  important  study.  The  work 
already  done  has  brought  into  prominence  the  effect  produced 
on  the  water  requirement  of  standard  crops  by  certain  conditions 
of  the  soil  in  which  the  crops  are  grown.  Among  these  may 
be  mentioned  the  moisture  content,  temperature,  fertility  and 
kind  of  soil.  The  influence  exerted  by  atmospheric  conditions 
has  likewise  been  studied  as  well  as  the  demands  of  the  plant  for 
water  at  critical  stages  of  its  growth.  What  is  urgently  needed 
at  this  stage  of  progress  is  the  standardization  of  the  methods  em- 
ployed so  that  the  results  may  be  more  readily  and  accurately  com- 
pared. In  devising  such  methods  it  is  essential  that  the  plants 
under  test  be  grown  as  nearly  as  possible  under  natural  conditions 
(Plate  VII)  in  order  that  the  farmer  may  know  how  much  water 
is  required  for  any  given  crop.  This  is  especially  needed  for 
irrigation  farming.  The  prevailing  custom  in  irrigated  districts 
as  has  been  pointed  out,  is  to  measure  the  duty  of  water  for  crops 
at  the  headgate  of  the  ditch  or  canal  but  the  rapid  increase  in 
the  value  of  water  is  drawing  attention  to  a  more  economical 
method.  In  recent  years  more  consideration  has  been  given  to 


150  USE  OF  WATER  IN  IRRIGATION 

the  actual  needs  of  each  crop  for  water  and  of  basing  the  net 
duty  thereon.  If,  for  example,  it  is  known  that  wheat  averaging 
40  bushels  or  2400  pounds  to  the  acre  with  the  accompanying 
straw  weighing  2900  pounds,  requires  350  pounds  of  water  to 
each  pound,  of  grain  and  straw,  the  net  duty  of  water  would  be 
about  0.68  acre-foot  per  acre.  To  this  minimum  allowance  should 
be  added  whatever  loss  is  sustained  in  the  carriage  of  the  water, 
deep  percolation,  run-off  and  evaporation  from  the  soil.  Many 
good  reasons  might  be  given  in  favor  of  this  method  of  determin- 
ing duty  of  water  in  irrigation  but  until  more  definite  knowledge 
is  obtained  concerning  the  actual  water  requirement  of  various 
crops  under  field  conditions  it  can  not  be  applied.  Viewed 
from  this  standpoint  that  method  of  experimentation  may  be 
said  to  be  best  which  approaches  nearest  to  natural  field  condi- 
tions. In  this  connection  the  writer  would  recommend  as  the 
result  of  his  experience  in  making  such  investigations,  that  the 
unit  of  soil  used  in  the  experiment  be  as  large  as  practicable  and 
that  the  vessel  containing  this  unit  be  placed  in  the  ground  and 
water-jacketed.  The  first  insures  a  near  approach  to  field  con- 
ditions and  the  second  controls  the  temperature.  It  is  a  well- 
known  fact  that  temperature  and  moisture  are  the  two  main 
conditions  which  cause  the  natural  vegetation  of  one  region  to 
differ  from  that  of  another.  Hence  it  follows  that  in  conducting 
experiments  of  the  kind  under  consideration  the  temperature  of 
the  soil  in  which  the  plants  grow  should  be  maintained  nearly 
equal  to  that  of  the  soil  in  the  field.  By  making  use  of  such 
water-jacketed  vessels  or  tanks  as  are  shown  in  Fig.  55  and 
placing  these  in  the  ground  with  their  tops  nearly  level  with 
the  surface,  the  temperature  of  the  soil  within  them  is  not  only 
kept  equal  or  nearly  equal  to  that  of  the  soil  without,  but  wind, 
sunshine  and  rain  exert  a  more  natural  influence  on  the  plants 
under  test. 

31.  Delivery  of  Water. ' — The  final  test  of  the  success  of  every 
irrigation  project  is  the  quality  of  the  service  rendered  to  ir- 
rigators  in  the  matter  of  water  delivery.  Adequate  water  de- 

*In  at  least  one  western  state,  California,  the  state  public  service  com- 
mission has  authority,  which  is  being  freely  exercised,  to  compel  adequate 
water  delivery  service  by  public  service  corporations  supplying  water  for 
irrigation. 


WASTE,  MEASUREMENT,  AND  DELIVERY      151 


livery  service  can  be  nothing  less  than  the  reasonably  prompt 
giving  to  each  irrigator  the  full  share  of  water  to  which  he  is  en- 
titled and  at  such  time  and  at  such  rate  of  flow  as  the  crops  to  be 

TABLE  No.  27 
Water  Requirement  of  Various  Standard  Crops 


Crop 

Location 

Experimenter 

Pounds 

water  per 
dry  matte 

pound  of 
r 

Max. 

Min. 

Mean* 

Wheat.  .  . 

Germany       

Sorauer  

708 

708 

Germany  
Germany 

Hellriegel  
Von  Seelhorst 

390 
333 

328 

339 
333 

India  

Leather  

544 

544 

Akron,  Colo. 

Briggs  &  Shantz  .  .  . 

534 

468 

507 

England 

Lawes 

235 

235 

Logan,  Utah  

Widtsoe  

489 

427 

458 

Davis,  Cal. 

Fortier  &  Beckett.  . 

359 

286 

326 

Oats 

Bozeman,  Mont  .  . 
Reno,  Nevada  — 

Germany 

Fortier  &  Gieseker  . 
Fortier  &  Peterson  . 

Wollny       

334 
395 

226 
309 

271 
360 

665 

Germany 

Sorauer 

600 

Germany  

Hellriegel  

464 

339 

401 

India 

Leather 

469 

Wisconsin 

King 

526 

502 

514 

Akron,  Colo  

Briggs  &  Shantz  .  .  . 

639 

598 

614 

Barlev 

England 

Lawes 

262 

258 

260 

Germany 

Wollny 

774 

Germany 

Sorauer 

490 

Germany 

Hellriegel     

366 

263 

297 

Germany  

Von  Seelhorst  

454 

295 

365 

India 

Leather 

468 

Wisconsin 

King  

401 

375 

388 

Akron,  Colo. 

Briggs  &  Shantz  .  . 

544 

527 

539 

Corn 

Germany 

Wollny 

233 

India 

Leather 

337 

Wisconsin    . 

King  

390 

305 

348 

Akron,  Colo    . 

Briggs  &  Shantz  .  .  . 

420 

319 

369 

Rye 

Germany 

Hellriegel 

438 

315 

377 

(  irniianv  

Von  Seelhorst  

700 

343 

469 

Akron,  Colo  

Briggs  &  Shantz.  .  . 

724 

1  I'nder  this  column  are  given  the  average  of  all  reliable  and  comparable 
tests. 


152 


USE  OF  WATER  IN  IRRIGATION 


TABLE  No.  27 
Water  Requirement  of  Various  Standard  Crops. — Continued 


Crop 

Location 

Experimenter 

Pounds 
( 

water  per 
Iry  matte 

pound  of 
r 

Max. 

Min. 

Mean 

Peas  

England  
Germany           .  .  . 

Lawes  
Wollny 

235 
416 

Germany 

Hellriegel 

353 

231 

292 

India  
Wisconsin  

Leather  
King 

563 

477 

Akron,  Colo. 

Briggs  &  Shantz 

800 

Potatoes  .  . 

Germany  
Wisconsin 

Von  Seelhorst  
King 

294 

268 

281 
423 

Alfalfa, 
1st.  Yr. 

Akron,  Colo  
Davis,  Cal  

Briggs  &  Shantz  .  .  . 
Fortier  &  Beckett.  . 

1265 

1005 

448 
1102 

2nd.Yr.. 

State          College, 
N.  M  

971 

889 

522 

757 

761 
823 

Clover 

Akron,  Colo  
England 

Briggs  &  Shantz  .  .  . 
Lawes 

1068 
251 

(red)  .  .  . 

Germany  

Hellriegel  

363 

297 

330 

Sugar 

Wisconsin  
Logan,  Utah  

King  
Widtsoe  

564 

398 

481 
497 

beets  .  .  . 
Rice  

Akron,  Colo.?  
India  

Briggs  &  Shantz  .  .  . 
Leather  

377 
811 

irrigated  require.  If  one  crop  is  mainly  irrigated  there  is  gen- 
erally little  difficulty  in  arranging  a  satisfactory  plan  of  water 
distribution  and  delivery,  for  in  the  main  each  irrigator  is  in  a 
like  position  with  all  of  his  neighbors  with  reference  to  the  quan- 
tity of  water  needed  per  acre  and  the  interval  between  irriga- 
tions. But  one-crop  agriculture  is  not  usual,  except  in  dis- 
tricts that  have  highly  specialized  crops,  so  that  the  irrigation 
manager  arranging  a  plan  of  water  distribution  and  delivery 
ordinarily  must  arrange  to  supply  water  to  diversified  plantings 
scattered  over  the  entire  project.  Some  crops,  like  small  fruits 
and  shallow-rooting  annual  field  crops,  are  usually  quite  sensitive 
to  comparatively  light  drought,  while  others,  as  alfalfa  and  or- 
chards on  deep  soil,  are  more  elastic  in  their  need  for  irrigation, 


WASTE,  MEASUREMENT,  AND  DELIVERY      153 

although  even  the  latter  are  best  served  by  regular  waterings, 
and  can  not  go  without  water  beyond  certain  varying  periods 
without  serious  damage.  Recent  investigations  indicate  that 
in  some  instances  the  character  of  the  product,  as  well  as  the 
quantity,  are  influenced  by  the  time  of  applying  water. 

RELATIONS  OF  SUPERINTENDENTS  OR  DITCH  TENDERS  AND  IRRI- 
GATORS. — Since  the  essential  condition  of  a  successful  irrigation 
system  is  adequate  water  delivery  service,  it  follows  that  those 
directly  in  charge  of  water  delivery  should  be  in  close  touch  with 
the  irrigators  served  and  thoroughly  understand  their  water 
requirements — how  much  water  the  different  crops  need  at 
each  irrigation,  how  often  irrigation  is  essential  in  the  case  of 
different  crops,  how  water  is  applied  to  the  various  soils  and  to 
the  various  crops  with  least  waste  and  most  efficiency.  Both 
superintendents  and  ditch  tenders  should  constantly  bear  in 
mind  that  an  entire  year  of  effort  on  the  part  of  the  farmer  may 
be  either  wholly  lost  or  very  adversely  affected  by  a  failure  in 
the  water  delivery  service;  also  that  the  service  that  is  acceptable 
to  one  irrigator  may  not  be  the  service  needed  by  another.  In 
order  that  both  ditch  tenders  and  irrigators  may  throughly 
know  their  relations  to  each  other,  the  plan  of  water  delivery  to 
be  followed  and  the  duties  and  rights  of  each  should  be  made  a 
part  of  the  printed  rules  and  regulations  of  the  system  and  be  in 
the  hands  of  every  ditch  tender  and  every  irrigator. 

REGULATIONS  GOVERNING  WATER  DELIVERY. — Every  irrigation 
project  is  in  some  degree  different  from  every  other  project 
and  the  necessary  and  proper  regulations  for  each  must  nec- 
essarily be  prepared  with  regard  to  the  particular  conditions 
present.  Still  there  are  certain  principles  of  regulation  that 
with  some  variation  are  desirable  for  any  well-managed  system 
and  the  most  important  of  these  have  been  outlined  by  Frank 
Adams,  in  charge  of  Irrigation  Investigations  of  the  Depart- 
ment of  Agriculture  in  California  in  the  following  paragraphs. 

(1)  "The  superintendent  and  the  ditch  tenders  working  under  him 
should  have  sole  control  of  all  gates,  checks,  and  turn-outs,  and  users 
should  be  prohibited  from  altering  them  without  definite  authority 
from  the  superintendent  or  ditch  tender,  of  course  excepting  cases  of 
emergency. 

(2)  "Every  irrigator  should  be  required  to  make  written  application 


154  USE  OF  WATER  IN  IRRIGATION 

for  any  water  wanted,  on  blanks  furnished  by  the  management,  the 
application  to  be  handed  to  the  ditch  tender  or  sent  directly  to  the  cen- 
tral office  of  the  system  a  sufficient  number  of  days — usually  1  to  3 — 
prior  to  the  time  water  is  needed.  This  enables  the  superintendent  and 
ditch  tenders  to  make  necessary  arrangements  for  getting  the  required 
flow  in  the  various  laterals. 

(3)  "Irrigators  should  be  given  ample  notice  of  the  time  water  is  to 
be  delivered  and  should  be  held  responsible  for  being  ready  to  receive  it 
at  the  time  set. 

(4)  "During  time  of  water  delivery  ditch  tenders  should,  wherever 
practicable,  be  required  to  be  within  ready  call  of  the  irrigators  receiving 
water.     This  is  especially  necessary  where  comparatively  large  irrigating 
heads  are  being  delivered  because  it  frequently  happens  that  for  one 
cause  or  other  the  delivery  must  be  temporarily  or  prematurely  stopped, 
in  which  case  the  ditch  tender  should  be  on  hand  to  care  for  the  water 
turned  back. 

(5)  "It  is  desirable,  but  not  always  practicable,  that  water  users 
should  make  all  complaijits  in  writing.     In  justice  to  the  users  the  rules 
should  require  that  all  complaints  filed  in  writing  shall  be  promptly 
investigated  by  the  superintendent. 

(6)  "The  rules  should  require  ditch  tenders  to  keep  careful  record,  on 
suitable  forms  furnished  by  the  management,  of  all  deliveries  made, 
such  record  to  state  the  time  of  beginning  and  ending  of  each  delivery, 
the  size  of  head  furnished,  the  acreage  irrigated,  and  the  crop  watered. 
On  some  systems  it  has  been  found  desirable  to  require  irrigators  to  give 
written  receipts,  preferably  in  the  ditch-tenders'  record  books,  for  de- 
liveries made. 

(7)  "Ditch  tenders  should  be  given  authority  in  the  rules  to  prevent 
all  avoidable  waste  from  the  irrigable  fields.     Where  water  is  repeatedly 
wasted  through  excessive  application  the  ditch  tenders  should  be  re- 
quired to  report  the  fact  in  writing  to  the  superintendent,  regardless  of 
whether  this  waste  is  depriving  some  other  user  of  water.    Excessive 
application  of  water  is  of  general  injury  through  causing  the  rise  of 
ground  water,  and  irrigators  should  at  the  start  be  taught  that  they  are 
entitled  to  no  more  water  than  the  crops  being  irrigated  require. 

(8)  "  The  rules  should  require  all  farm  ditches  to  be  of  proper  capacity 
to  carry  without  undue  waste  the  water  delivered.     They  should  also 
require  that  they  be  kept  in  good  repair  throughout  the  delivery  season. 

(9)  "Authority  should  be  given  in  the  rules  for  placing  locks  on  all 
turn-out  gates  when  this  is  found  necessary. 

(10)  "The  superintendent  should  be  given  full  authority  to  discon- 
tinue water  delivery  to  any  irrigator  who  wilfully  and  repeatedly  dis- 
regards the  established  regulations  of  the  system. 


WASTE,  MEASUREMENT,  AND  DELIVERY      155 

(11)  "It  is  usually  desirable  to  establish  a  definite  irrigating  season 
within  which  water  will  be  available.     In  such  cases  the  limits  of  the 
irrigation  season  should  be  stated  inrthe  rules.     This  should  not  mean 
that  where  feasible  water  is  not  to  be  run  at  other  times.    Sometimes  it 
is  very  desirable  that  irrigation  should  occur  during  the  whiter  months 
which  are  never  included  in  a  regular  irrigation  season,  and  where 
desirable,  this  should  be  encouraged.     In  the  Southwest  some  irrigation 
systems  usually  carry  water  for  10  or  12  months  of  each  year. 

(12)  "The  rules  should  specify  the  duties  of  ditch  tenders  in  the 
matter  of  patrol  and  care  of  canal  banks  and  structures,  and  also  in  the 
matter  of  reports  to  their  superintendent  and  of  their  proper  relations 
to  irrigators." 

PLAN  OF  WATER  DELIVERY. — Attention  has  already  been  called 
to  the  necessity  for  adopting  a  plan  of  water  distribution  and 
deliver}'  that  will  give  water  to  each  irrigator  at  the  time  and  in 
the  quantity  required  by  the  crops  to  be  irrigated.  While  very 
large  farms,  as  of  a  full  section  of  land,  can  sometimes  profitably 
use  a  continuous  flow  of  water,  it  has  become  almost  universally 
recognized  that  delivery  by  some  plan  of  rotation  is  by  far  the 
best  plan  to  follow  and  the  only  plan  that  is  generally  economical. 
It  eliminates  the  wasteful  use  of  small  heads,  there  being  much 
greater  economy,  within  reasonable  limits,  in  using  a  large  enough 
head  to  get  over  land  quickly  than  in  using  for  a  longer  time  such 
a  small  head  as  continuous  flow  would  require. 

The  simplest  plan  of  rotation  delivery  is  one  hi  which  each 
irrigator  may  receive  water  during  each  run  for  a  certain  definite 
length  of  time  for  each  acre  irrigated,  all  delivery  heads  to  be  of 
equal  quantity.  The  runs  may  be  arranged  to  begin  and  end 
at  such  times  as  may  be  fixed  during  the  season,  the  size  of  heads 
also  being  changed  from  time  to  time  as  the  total  supply  available 
for  delivery  makes  desirable.  In  this  simple  plan  the  various 
runs  are  usually  not  definitely  scheduled  at  their  beginning  to 
show  the  time  of  delivery  to  each  individual  irrigator.  Instead, 
as  the  runs  proceed  each  irrigator  is  notified  in  advance  as  to  the 
approximate  time  delivery  may  be  expected,  water  being  allowed 
to  each  until  his  farm  is  well  watered  or  until  delivery  has  con- 
tinued for  the  apportioned  time  for  each  acre  in  the  farm.  Breaks 
or  other  interruptions  merely  delay  the  completion  of  the  runs 
during  which  they  occur.  This  plan  of  delivery  is  quite  common 


156  USE  OF  WATER  IN  IRRIGATION 

i 

on  large  systems,  especially  in  the  earlier  periods  of  their 
operation. 

A  more  complete  plan  of  rotation  delivery,  involving  full 
seasonal  schedules,  by  which  each  irrigator  knows  at  the  be- 
ginning of  each  season  the  hour  and  day  when  he  will  receive 
water  during  every  run,  is  not  uncommon  on  some  of  the  older 
irrigating  systems,  and  especially  on  some  of  the  smaller  systems, 
as  in  southern  California,  under  which  one  crop  or  one  system 
of  plantings  chiefly  occur.  For  such  a  system  a  reasonably 
regular  supply  of  water  in  the  main  canal  is  necessary,  and,  ex- 
cept on  some  of  the  smaller  systems,  this  does  not  frequently 
occur.  On  the  small  southern  California  systems  using  this 
seasonal  schedule  plan  water  is  usually  delivered  to  each  irrigator 
once  every  30  days,  or  a  one-half  supply  is  delivered  every 
15  days,  the  last  day  in  31-day  months  not  being  counted  in 
making  up  the  schedules.  On  one  large  system  in  Utah  a  con- 
tinuous flow  of  at  least  2.1  second-feet  is  maintained  in  each  con- 
sumer's lateral,  these  laterals  having  been  laid  out  to  permit  of 
this,  and  each  irrigator  receives  water  at  this  rate  1  hour  each 
week  for  each  acre  irrigated,  the  same  schedule  being  followed 
substantially  year  after  year. 

The  above-mentioned  rotation  plans,  or  modifications  of  them, 
are  suited  to  systems  delivering  water  on  an  acreage  basis.  But 
when  water  is  paid  for  according  to  quantity  received  a  different 
rotation  plan  is  necessary,  where  rotation  is  followed.  Paying 
for  the  quantity  of  water  received  results  in  a  considerable  varia- 
tion in  the  quantity  used  per  acre,  both  as  between  individual 
irrigators  and  during  the  season  in  the  case  of  single  irrigators. 
This  makes  regular  individual  delivery  schedules  impracticable 
but  does  not  alter  the  desirability  of  rotating  between  the  various 
parts  of  a  system  in  order  to  do  away  with  running  less  water 
in  laterals  than  they  are  designed  to  carry  economically.  Even 
where  water  is  paid  for  on  an  acreage  basis  this  rotation  between 
laterals,  especially  in  times  of  shortage,  is  desirable  for  the  same 
reason. 

On  some  systems  continuous  flow  to  individuals,  who  in  turn 
rotate  to  some  extent  between  each  other,  constitutes  another 
rotation  plan.  Sometimes,  even  when  the  main  delivery 
schedule  provides  rotation  between  individuals,  two  or  more  of 


H MN7V-, '.  MEASUREMENT,  AND   DELIVERY      157 

these  individuals  carry  the  plan  even  further  by  rotating  among 
themseh 

While  delivery  on  demand  sometimes  goes  with  a  modified 
plan  of  rotation,  some  systems  are  so  arranged  as  to  distributaries 
and  crops  grown  that  it  is  most  satisfactory  to  have  water 
continuously  subject  to  demand  in  nearly  every  part  of  it. 
With  an  all-reservoir  supply  this  is  an  excellent  plan,  no  water 
needing  to  be  turned  into  the  distributaries  unless  previously 
called  for.  Where  the  demand  for  water  is  sufficiently  even  so 
that  the  needs  and  the  supply  can  be  balanced  so  closely  in  ad- 
vance that  practically  no  water  is  wasted,  as  is  the  case  with 
some  of  the  southern  California  systems  irrigating  citrus  fruits, 
the  plan  becomes  an  almost  ideal  one,  especially,  as  is  the  case 
with  many  of  the  southern  California  systems,  when  the  water 
distribution  on  the  farms  is  through  underground  pipes. 

Possibly  of  equal  importance  with  the  plan  of  water  delivery 
to  be  followed  is  the  plan  of  charges  to  be  made  for  the  water 
delivered.  Authorities  are  now  almost  a  unit  in  holding  that 
water  should  be  charged  for  according  to  quantity  delivered 
rather  than  according  to  acreage  irrigated.  Experience  shows 
that  a  much  higher  duty  of  irrigation  water  is  reached  under  the 
former  of  these  two  methods.  In  recent  years  there  has  gradually 
grown  up  the  practice  of  making  a  flat  acre  charge  for  the  first 
acre-foot  or  for  the  first  1.5  or  2  acre-feet  delivered,  with  a 
quantity  charge  for  water  delivered  in  excess  of  that.  This  is 
an  admirable  principle  if  the  quantity  permitted  under  the  flat 
acre  rate  is  not  made  too  large.  The  importance  of  this 
matter,  however,  is  more  fully  discussed  in  Art.  26. 

DELIVERY  FORMS  AND  RECORDS. — Reference  has  already  been 
made  to  the  desirability  of  ditch  tenders  keeping  accurate  record 
of  all  deliveries  of  water  to  individual  irrigators.  In  the  earlier 
years  of  a  project  it  is  sometimes  very  difficult  for  those  operat- 
ing irrigation  systems  to  find  time  to  keep  many  records.  A 
full  record  system  of  water  distribution  and  delivery  should,  how- 
ever, be  begun  at  the  earliest  possible  time.  The  essential  records 
in  this  connection  would  cover  (a)  the  daily  flow  in  the  main 
canal  of  the  system  and  the  daily  amount  available  in  reservoirs, 
(b)  the  daily  diversions  from  the  main  canal  into  the  principal 
laterals,  (c)  the  daily  deliveries  to  individuals,  (d)  a  delivery 


158  USE  OF  WATER  IN  IRRIGATION 

ledger  account  for  each  irrigator  where  the  quantities  delivered 
are  charged  for,  and  (e)  ditch  tender's  diaries.  Many  private, 
cooperative,  and  district  irrigation  systems,  and  also  the  various 
projects  of  the  United  States  Reclamation  Service,  have  worked 
out  very  complete  records  and  forms.  For  descriptions  of  these 
forms  reference  is  made  to  Bui.  229  of  the  Office  of  Ex- 
periment Stations,  U.  S.  Department  of  Agriculture  by  Frank 
Adams,  and  to  the  operation  and  maintenance  manual  of  the 
Reclamation  Service. 

DELIVERY  FORCE  REQUIRED. — The  first  essential  of  a  water  de- 
livery force  in  irrigation  systems  is,  as  previously  pointed  out, 
that  it  shall  understand  the  needs  of  the  water  users.  While 
it  is  almost  always  necessary  that  the  ditch  tenders  charged  with 
water  delivery  shall  also  patrol  the  canal  system  for  breaks  and 
make  all  ordinary  repairs  that  can  be  attended  to  in  connection 
with  their  other  duties,  their  duties  in  connection  with  water 
delivery  should  be  paramount  to  maintenance  and  on  large 
systems  at  least  their  water  delivery  activities  should  be  directed 
by  a  head  water  master  not  connected  with  the  maintenance 
work  of  the  system.  The  number  of  miles  patroled  per  day  by 
ditch  tenders  may  vary  from  5  or  6  to  about  20.  The  average 
number  of  miles  traveled  on  fifteen  projects  of  the  U.  S.  Reclamation 
Service  is  given  by  F.  W.  Hanna  as  22.4,  with  the  average  number 
of  users  served  daily  per  ditch  tender  as  26.2.  An  authority 
on  systems  in  Montana  gives  10  to  12  miles  per  day  as  the  usual 
length  of  main  canal  patroled  daily  by  each  ditch  tender,  with 
5  or  6  miles  the  length  of  section  patroled  on  laterals  while  at  the 
same  time  about  fifteen  private  turn-outs  being  cared  for.  One 
large  system  in  Wyoming  employs  one  ditch  tender  to  cover  each 
5  to  10  miles  of  main  canal  and  all  laterals  leading  from  it.  The 
average  length  of  main  canal  and  laterals  served  per  ditch  tender 
under  four  important  systems  in  California  is  11.7  miles.  On 
one  large  system  in  Colorado  it  is  23.5  miles.  On  another  in 
the  same  general  section  it  is  13.3.  On  three  large  Utah  systems 
it  is  19.4  miles.  These  figures  indicate  a  wide  difference  which 
is  probably  more  apparent  than  real  so  far  as  pertains  to  ser- 
vice performed,  owing  to  the  different  duties  and  the  different 
number  of  users  served  and -in  the  care  with  which  deliveries 
are  made. 


WASTE,  MEASUREMENT,  AND  DELIVERY      159 

THE  DELIVERY  "HEAD." — How  large  the  irrigating  heads 
should  be  is  a  question  of  immediate  and  practical  interest  to 
every  irrigation  manager.  No  rule  can  be  laid  down  and  practice 
varies  widely.  With  continuous  flow  as  little  as  a  single  miner's 
inch,  or  about  0.02  second-foot,  has  sometimes  been  delivered 
as  an  irrigating  head  for  furrow  irrigation  on  2-acre  or  3-acre 
tracts,  but  such  small  heads  are  altogether  unusual.  In  the 
citrus  orchards  of  southern  California  where  furrow  irrigation 
is  practised  and  where  the  irrigation  water  is  distributed  in  under- 
ground pipes  or  flumes  heads  of  10  to  50  inches,  or  0.20  to  1  second- 
foot  are  perhaps  most  common.  In  Modesto  and  Turlock  irri- 
gation districts,  California,  the  practice  is  to  give  heads  of  from 
15  to  20  and  sometimes  30  second-feet  for  from  20  to  30  minutes 
per  acre  at  each  run,  yet  irrigators  themselves  often  split  the  full 
heads  into  several  smaller  heads.  These  California  figures 
represent  the  two  extremes.  As  a  rule  such  large  heads  as  20 
to  30  second-feet  are  excessive  and  while  theoretically  economical 
in  that  they  largely  prevent  uneven  distribution  in  alfalfa  checks, 
in  the  main  they  are  believed  to  foster  wasteful  practice.  The 
smaller  heads  are,  of  course,  economical  in  special  cases  only. 
In  most  of  the  mountain  states  with  continuous  flow  the  irri- 
gating head  is  based  on  the  number  of  water  shares  owned  by  each 
irrigator  and  may  be  as  little  as  10  inches  and  in  some  cases  as 
much  as  100  inches  or  more.  Under  the  largest  system  in  Utah 
the  stream  delivered  is  usually  from  2  to  4  second-feet.  Accord- 
ing to  figures  furnished  by  F.  W.  Hanna  on  the  projects  of  the 
Reclamation  Service  practice  varies  widely  with  the  different 
conditions  met,  as  much  as  12  to  20  second-feet  being  given  as  a 
maximum  delivery  head  on  some  of  the  projects,  with  average 
deliveries  on  the  same  projects  varying  between  3  and  7.5  cubic 
feet  per  second.  On  Reclamation  Service  projects  using  the 
smaller  class  of  heads,  as  on  the  Boise,  Uncompahgre,  Huntley, 
Sun  River  and  Shoshone  projects,  the  maximum  heads  vary 
from  2.5  to  4  second-feet  and  the  average  from  0.75  second-feet 
to  2  second-feet. 

On  the  whole,  the  above  data  indicate  that  the  head  adopted 
on  any  system  must  be  determined  with  reference  to  the  par- 
ticular conditions  found.  The  soil  and  crop  irrigated  must 
govern,  and  distribution  systems,  including  delivery  gates, 


160  USE  OF  WATER  IN  IRRIGATION 

must  be  designed  to  permit  using  the  head  that  is  the  most 
economical.  In  general,  the  greater  the  slope  and  the  more 
porous  the  soil,  the  smaller  should  be  the  delivery  head  adopted. 
Furrow  irrigation  accomplishes  the  best  results  by  the  use 
of  relatively  small  streams  after  the  furrows  have  once  become 
wetted,  and  the  head  delivered  can  only  be  determined  according 
to  the  number  of  furrows  it  is  convenient  to  care  for  during 
irrigation  at  one  time.  In  irrigating  both  grains  and  alfalfa 
in  the  mountain  states  the  characteristic  slope  of  the  irrigated 
lands  usually  prevents  applying  in  excess  of  2  to  4  second-feet 
at  one  time,  while  the  flatter  slopes  and  more  sandy  soils  of 
such  places  as  the  Great  Valley  of  California  and  of  the  South- 
west make  heads  as  large  as  10  to  15  second-feet  economical 
of  both  time  and  water  where  check  flooding  is  practised,  much 
smaller  heads  being  necessary  for  furrow  irrigation. 

A  description  of  the  more  common  devices  used  for  the  meas- 
urement of  deliveries  may  be  found  under  Art.  27. 

32.  Injurious  Mineral  Salts. — Portions  of  all  soils  are  con- 
tinuously being  made  soluble  by  numerous  agencies.  Abundant 
rains,  which  percolate  through  the  soils  of  the  earth's  humid 
regions  carry  these  soluble  materials  as  they  are  formed,  into 
the  rivers,  lakes,  and  oceans.  Vast  areas,  however,  have  in- 
sufficient rainfall  to  leach  away  the  soluble  salts,  thus  giving 
rise  to  excess  accumulation  of  these  materials  in  arid  soils. 
" Alkali,"  a  term  commonly  given  to  all  excess  mineral  salts, 
usually  exists  in  the  form  of  chloride,  sulphates,  and  carbonates 
of  sodium,  calcium,  and  magnesium.  Broadly  speaking,  the 
world  over,  alkali  salts  consist  chiefly  of  sodium  chloride,  (NaCl), 
common  salt;  sodium  sulphate  (Na2SO4),  Glauber  salt;  and 
sodium  carbonate  (Na2CO3)  sal  soda.  The  latter  is  commonly 
spoken  of  as  " black  alkali"  since  it  dissolves  organic  matter 
and  thus  gives  the  soil  surface  a  dark  color,  while  the  other 
salts  which  are  less  harmful  to  plants,  form  a  white  crust  on  the 
soil  and  are  hence  classed  as  "  white  alkali." 

While  it  is  very  difficult  to  give  maximum  per  cents,  of  plant 
tolerance  to  alkali,  Hilgard's  limits  of  0.1  per  cent,  sodium 
carbonate,  0.25  per  cent,  sodium  chloride  and  0.50  per  cent, 
sodium  sulphate,  observed  for  cereals  in  sandy  loam  soil  are 
valuable  as  a  general  guide.  In  clay  soils,  the  injurious  pud- 


WASTE,  MEASUREMENT,  AND  DELIVERY      161 

dling  or  breaking  down  of  crumb  structure,  especially  by 
sodium  carbonate,  makes  the  limits  very  much  less. 

Much  of  the  future  success  in  the  cultivation  of  alkali  lands 
undoubtedly  depends  upon  the  use  of  plants  resistant  to  soluble 
salts.  The  date  palm,  according  to  Swingle  (Bui.  53,  Bureau 
of  Plant  Industry,  U.  S.  Dept.  Agr.)  is  the  most  resistant  of 
cultural  plants.  Kafir  corn,  sorghum,  sugar  beets,  barley,  rye, 
mature  alfalfa,  and  asparagus  are  among  the  most  resistant 
of  ordinary  crops,  while  wheat  and  oats  tolerate  very  little 
alkali.  Leguminous  plants  are  as  a  class  sensitive,  although 
alfalfa  and  vetch  are  quite  resistant.  Hilgard  reports  that 
carrots,  onions,  and  potatoes  produce  normal  yields  in  soils 
strongly  alkaline,  but  that  the  quality  of  the  crops  is  badly 
affected.  Grapes,  olives,  almonds,  and  figs  are,  in  the  order 
named,  the  most  resistant  fruit  crops;  while  oranges,  pears  and 
apples  are  moderately  tolerant;  and,  prunes,  peaches,  apricots 
and  lemons  rather  sensitive. 

Proper  treatment  of  alkali  soils  will  materially  lessen  the 
injurious  effects  of  the  excess  soluble  salts.  Immediately  after 
each  irrigation  large  volumes  of  water  are  evaporated  from 
the  soil.  A  total  loss  of  3  acre-inches  per  acre  in  a  period 
of  9  days,  causing  a  deficiency  in  moisture  to  a  depth  of  10 
feet  has  been  observed  by  Widtsoe.  As  moisture  moves  up- 
ward in  the  soil,  large  quantities  of  soluble  materials  are  carried 
with  it  to  the  surface  where  the  salts  are  deposited,  as  the 
water  passes  off  in  vapor  form.  Suppose  that  a  soil  containing 
only  0.05  per  cent,  soluble  salts,  an  ordinary  amount  in  many 
productive  lands,  should  have  the  entire  amount,  contained  to 
a  depth  of  10  feet,  deposited  in  the  surface  6  inches.  The 
surface  content  would  be  twenty  times  as  great  as  before  evapo- 
ration took  place,  thus  making  a  total  amount  of  1  per  cent, 
which  is  beyond  plant  tolerance.  As  a  matter  of  fact,  many 
soils  in  which  " alkali"  has  been  unsuspected,  have  been  rendered 
worthless  in  just  this  manner.  Clearly  then  irrigators  must 
reduce  evaporation  from  their  soils. 

Soils  naturally  alkaline,  or  those  rendered  such  by  faulty 
irrigation  may  be  improved  by  (1)  cropping  with  resistant 
plants,  (2)  removing  surface  incrustation,  (3)  turning  under 


162  USE  OF  WATER  IN  IRRIGATION 

surface  soils,  (4)  chemical  treatment,  and  (5)  leaching  by  flood- 
ing and  drainage. 

About  one-fifth  of  the  dry  weight  of  Australian  salt  brush 
and  Russian  thistle  is  ash  or  salt  compounds,  hence  with  5 
tons  of  dry  matter  harvested,  1  ton  of  salt  would  be  removed. 
This  may,  in  time,  give  some  improvement.  Moving  the 
surface  soil  can  be  economically  practised  only  on  small  areas 
or  under  other  conditions,  especially  favorable.  Turning  it 
under  will  distribute  the  salts  over  a  large  area,  and  thus  give 
at  least  temporary  relief,  while  plants  germinate  and  establish 
a  root  system  to  great  depths.  Chemical  treatment,  which 
is  applied  only  to  " black  alkali"  consists  in  adding  calcium 
sulphate  in  amounts  which  depend  on  the  amount  of  sodium 
carbonate  in  the  soil,  and  vary  from  a  few  hundred  pounds  to 
several  tons  per  acre.  This  method  is  valuable,  even  when 
leaching  is  contemplated,  since  it  is  very  difficult  to  leach  sodium 
carbonate.  The  less  harmful  sodium  sulphate,  formed  by 
adding  calcium  sulphate,  leaches  with  comparative  ease.  Its 
beneficial  effects  are  reversed,  however,  if  soils  are  irrigated 
to  excess.  Moreover,  the  noxious  " black  alkali"  is  actually 
formed  in  ordinary  soils  when  they  are  swamped  by  heavy  ir- 
rigation. Ultimately,  however,  leaching  the  excess  salts  by 
drainage  is  the  only  permanent  method  of  reclamation. 1  This 
process  was  successfully  tried  in  the  vineyards  of  Fresno  County, 
California,  by  V.  M.  Cone  and  the  writer  in  1907  and  1908. 
The  upper  4  feet  of  soil  before  being  treated  contained  on 
an  average  about  2/10  of  1  per  cent,  of  soluble  salts.  After 
drain  pipes  had  been  laid  in  the  vineyard,  the  surface  formed 
into  checks  and  each  check  flooded  twice  to  a  depth  of  12  inches, 
the  percentage  of  soluble  salts  was  reduced  to  about  4/100  of  1 
per  cent. 

33.  The  Use  of  Saline  Waters  in  Irrigation. — Large  amounts 
of  soluble  salts  occur,  not  only  in  the  soils,  but  also  in  the  streams, 
lakes,  and  underground  waters  of  the  earth's  arid  region.  The 
importance  of  plant  tolerance  to  saline  irrigation  waters  is  there- 
fore obvious.  Some  valuable  observations  have  been  made  in 
connection  with  the  use  of  such  waters  for  irrigation,  but  no  sys- 

1  See  Drainage  of  Irrigated  Lands  in  the  San  Joaquin  Valley,  Bui.  217, 
O.  E.  S.,  U.  S.  D.  A. 


WASTE,  MEASUREMENT,  AND  DELIVERY      163 


tcmatic  field  experiments  have  been  conducted  for  the  purpose  of 
determining  plant  tolerance  to  them.  Reports  of  water  analysis 
usually  include  all  dissolved  solids,  but  for  agricultural  purposes 
analyses  of  water  for  sodium  carbonate  (Na2CO3);  sodium 
chloride  (NaCl);  and  sodium  sulphate  (NaSO)  will  give  a  good 
index  to  its  value.  The  amount  of  mineral  salts  contained  in 
water  is  commonly  reported  in  parts  per  100,000. 

The  following  classification  of  river  waters,  made  by  Stabler 
(Water  Supply  Paper  No.  274  and  Engineering  News  of  July 
14,  1910)  furnishes  irrigators  a  general  guide  in  the  use  of  saline 
waters. 

TABLE  No.  28 

Table  Showing  Classification  of  River  Waters  for  Irrigation  Purposes  Based 
upon  Amount  and  Composition  of  Dissolved  Solids 


Class  Name  of  river 

Place  of  sampling 

Dissolved 
solids, 
parts  per 
100,000 

Radicals  in  per  cent, 
dissolved  solids 

Carb. 
(CO3) 

Bicarb.]  Chlor. 
(HCOs)]    (Cl) 

Fair  Rio  Grande. 

El  Paso,  Texas  

69.9 
70.7 
53.4 
73.6 

230.0 
317.0 
272.0 

359.0 
913.0 

0.10 

0.28 
0.00 
0.04 

0.00 
0.00 
0.01 

0.04 
0.01 

34.0 
33.0 
36.0 
35.0 

6.2 
6.1 
5.7 

5.3 

1.7 

15.0 
18.0 
30.0 
30.0 

9.5 
12.0 
17.0 

33.0 
38.0 

Fair  Colorado 

Yuma,  Ariz. 

Fair  Salt  River  
Fair  Gila  River  . 

Roosevelt,  Ariz 

San  Carlos,  Ariz  

Near  Mangum,  Okla.. 
Near  Olustee,  Okla... 
Near  Carlsbad,  N.  M.. 

Near  Headrick,  Okla  .  . 
Near  Mangum.  Okla.. 

Fair   'Salt   Fork    of 
Red  River  

Poor  Turkey  Creek..  . 
Poor  Pecos  River  
Poor  North  Fork  of 
Red  River 

Bad  Elm  Fork  of  Red 
River  

The  calcium  (Ca);  sulphate  (S04)  sodium  (Na)  and  other 
radicals  are  omitted  from  the  table,  hence  the  sum  of  the  per 
cent,  columns,  as  given  above  will  never  equal  100.  Note  that 
the  Salt  Fork  of  Red  River,  which  contains  a  total  of  230  parts 
dissolved  matter  per  100,000  is  classed  as  fair.  When  it  is 
observed  that  none  of  this  material  is  carbonate,  only  6.2  per  cent. 
Bicarbonate  and  9.5  per  cent,  chlorine,  the  reason  for  the  classifi- 
cation is  obvious.  The  waters  of  these  rivers,  excluding  the  last 
two,  have  all  been  successfully  used  for  irrigation.  That  special 

1  52  per  cent,  of  D.  S.  (S0<)  and  18  per  cent.  (Ca). 


164 


USE  OF  WATER  IN  IRRIGATION 


precautions  are  necessary  to  permanently  maintain  the  pro- 
ductive capacity  of  soils  in  connection  with  the  use  of  such  waters 
is  evident  in  view  of  experience  in  various  localities  as  briefly 
mentioned  in  the  following  paragraph. 

Certain  orchard  soils,  irrigated,  according  to  Forbes,  with 
water  taken  from  the  Salt  River,  Arizona,  which  contained  soluble 
salts  varying  in  amount  from  52  to  157  with  a  mean  of  107  parts 
per  100,000,  accumulated  from  0.111  per  cent,  to  0.426  per  cent, 
in  a  period  of  about  10  years  (Arizona  Bui.  44,  p.  116). 
Two  samples  of  Wyoming  water  which  contained  5.71  and  23.58 
parts  alkali  salts  per  100,000,  before  irrigation,  were  shown  by 
Slossen  from  analysis  of  the  waste  waters,  to  have  made  annual 
deposits  in  the  upper  3  feet  of  soil  which  would  in  a  period 
of  10  years,  have  amounted  to  0.067  and  0.278  per  cent,  re- 
spectively (Wyo.,  Bui.  24,  pp.  114  and  117).  The  Bureau  of 
Soils,  U.  S.  Dept.  of  Agri.,  speaking  of  conditions  in  the  Pecos 
Valley,  New  Mexico,  said,  "Five  hundred  parts  of  soluble  matter 
may  be  taken  as  the  extreme  limit  of  endurance  for  plants,  while 
250  to  300  mark  the  danger  point  at  which  the  results  of  the  use 
of  water  are  very  uncertain. "  That  this  estimate  is  conserva- 
tive, seems  evident  in  view  of  the  fact  that  for  centuries  past 
waters  containing  from  400  to  800  parts  per  100,000  have  been 
successfully  used  in  crop  production,  according  to  Means,  by 
the  Arabs  in  the  Algerian  Oases. 

The  remarkable  success  attained  by  the  Arabs  with  such 
waters  is  dependent  upon  frequent,  heavy  application  of  water 
and  thorough  drainage  by  open  ditches  or  tiles  (Bureau  of 
Soils,  Cir.  10).  The  efficiency  of  frequent  flooding  is  well 
illustrated  in  the  following  table  after  Forbes  showing  the  relative 
alkali  content  in  furrows  and  rows  subsequent  to  the  use  of  saline 
water  in  furrow  irrigation. 

TABLE  No.  29 


Depth  in  feet 

Uncultivated  tree 
row 

Temporary  ridges 

Furrows  flooded 
every  8  days 

Per  cent,  of  alkali 
in  soil 

Per  cent,  of  alkali 
in  soil 

Per  cent,  of  alkali 
in  soil 

1 

2 

3 

0.305 
0.099 
0.092 

0.295 
0.070 
0.055 

0.043 
0.045 
0.046 

WASTE,  MEASUREMENT,  AND  DELIVERY      165 

Note  that  the  uncultivated  row  contains,  in  the  first  foot,  7 
times  as  much  salt  as  the  furrow,  and  in  the  second  and  third, 
only  twice  as  much  as  the  soil  under  the  furrow.  Forbes  noted 
further  that  the  crest  of  a  ridge  in  a  strawberry  plat  contained 
0.20  per  cent,  in  the  surface  foot  as  compared  to  0.061  per  cent, 
in  the  bottom  of  the  adjacent  furrow.  Hilgard  observed  that  in 
a  period  of  3  years,  water  containing  170  parts  of  soluble  salts 
per  100,000,  caused  complete  defoliation  of  orange  trees  near 
Corona,  California,  and  increased  the  per  cent,  of  salts  in  the  soil, 
originally,  0.0174  four  times.  He  says  further  that  the  upper  limit 
under  ordinary  practice  in  California  is  120  parts.  Water  from 
artesian  wells  containing  from  175  to  200  parts  mineral  salts 
per  100,000  have  been  successfully  used  for  irrigation  in  South 
Dakota. 

The  general  statement  of  permissible  per  cents,  of  mineral 
matter  in  irrigation  water  involves  a  knowledge  of  the  character 
and  relative  proportion  of  the  alkali  salts;  the.  crops  grown;  the 
soil  texture,  depth,  and  original  alkali  content;  methods  of  irri- 
gation; and  drainage  facilities.  From  the  foregoing  examples  it 
is  obvious  that,  although  the  parts  of  tolerable  salts  differ  widely, 
under  various  conditions,  evaporation  must  be  reduced  to  a  mini- 
mum and  drainage  provided  when  saline  waters  are  used.  Irri- 
gation should  be  quickly  followed  by  cultivation,  especially  where 
the  furrow  method  is  employed.  Practical  experience  and  chem- 
ical analysis  agree  in  emphasizing  liberal  flooding  and  thorough 
drainage  where  saline  waters  must  be  used. 

In  case  natural  drainage  is  inadequate  and  artificial  drain- 
age impractical,  the  following  method  adopted  by  Israelson 
of  calculating  the  number  of  acre-feet  of  water,  containing  a 
given  amount  of  salt,  which  can  be  safely  added  to  the  soil  may 
be  valuable  in  helping  irrigators  to  interpret  an  analysis  of 
the  water  used.  It  assumes  that  all  of  the  alkali  salts  con- 
tained in  the  irrigation  water  remain  in  the  soil.  An  example 
will  make  it  clear.  Suppose  the  alkali  content  is  150  parts 
sodium  chloride  per  100,OQO  of  water,  the  irrigation  water 
penetrates  to  a  depth  of  6  feet,  and  that  a  cubic  foot  of  soil 
weighs  1.32  times  the  weight  of  a  cubic  foot  of  water,  a  rela- 
tion generally  true.  Let  N  equal  the  number  of  acre-feet  per 
acre  that  can  be  safely  added.  By  Art.  32  the  maximum 


166  USE  OF  WATER  IN  IRRIGATION 

amount  of  sodium  chloride  that  ordinary  plants  can  tolerate 
in  the  soil  is  0.25  per  cent.,  therefore  the  greatest  number  of 
pounds  permissible  in  6  acre-feet  of  soil  is 

0.25  X  1.32  X  62.5  X  43,560  X  6 
100 

The  number  of  pounds  chloride  in  1  acre-foot  of  water 
would  be  °'15°  X  fop  X  43>56°  as  ISO  parts  per  100,000  =0.150 

per  cent.,  62.5  the  weight  of  1  cubic  foot  of  water,  and  43,560 
the  area  of  1  acre  in  square  feet.  Hence, 

0.25  X  1.32  X  62.5  X  43,560  X  6 
1.150  X  52.5  X  43,560 

If,  therefore,  2  acre-feet  of  water  are  used  annually,  a  period 
of  6  to  7  years  would  render  the  soil  unproductive.  From  the 

1.32  X  Ps  X  D  . 
above  discussion,  the  general   formula  TV  =  -      — -5 -  is 

easily  deduced  where  Ps  equals  the  permissible  per  cent,  of 
salt  in  the  soil,  Pw  the  per  cent,  of  salt  contained  in  the  irri- 
gation water,  and  D  the  mean  depth  in  the  soil  to  which  water 
penetrates. 

34.  Drainage  of  Irrigated  Farm  Lands. — The  drainage  of 
land  in  an  arid  region  differs  in  many  essential  features  from 
the  drainage  of  land  in  a  humid  region.  In  the  former  the  soil 
in  its  natural  state,  except  near  the  surface,  has  been  continuously 
dry  for  ages.  No  percolating  water  has  passed  through  it  and 
in  consequence  no  drainage  arteries  have  been  formed  within 
its  mass.  It  is  not  until  water  is  conveyed  and  distributed  in 
artificial  channels  over  the  land  that  these  conditions  are  changed. 
These  changes  are  often  very  radical  in  character.  The  river 
may  no  longer  flow  in  its  natural  channel  but  be  taken  out  and 
spread  over  large  areas  of  dry  soil.  This  soil  and  the  numerous 
earthen  channels  which  convey  the  water  permit  a  large  part 
to  percolate  and  otherwise  pass  through  the  top  layer  of  soil. 
Gravity  and  capillarity  draw  this  escaping  water  lower  and 
lower  until  some  impervious  stratum  is  reached  along  which 
it  passes  to  lower  levels.  The  intercepting  of  this  waste  or 
seepage  water  from  the  irrigated  field  and  ditch  forms  an  im- 
portant feature  in  the  drainage  of  arid  lands. 


WASTE,  MEASUREMENT,  AND  DELIVERY      167 

Another  feature  of  even  greater  importance  is  the  presence 
of  mineral  salts  known  as  alkali  in  amounts  larger  than  the 
ordinary  crops  can  tolerate;  The  greater  part  of  these  salts 
have  to  be  removed  and  drainage  systems  are  planned,  not 
only  to  lower  the  ground-water  level  but  to  remove  the  harmful 
accumulation  of  alkali. 

Charles  F.  Brown  divides  irrigated  lands  needing  drainage 
into  three  classes  (Farmers'  Bui.  371).  (1)  Those  injured 
by  excess  of  water  only,  (2)  those  affected  by  an  excess  of  both 
water  and  alkali,  (3)  those  having  an  excess  of  alkali  only. 

The  Deer  Lodge  Valley  in  Montana  is  an  example  of  the  first 
class.  The  extensive  drainage  operations  now  in  progress  under 
the  supervision  of  Dr.  H.  C.  Gardner  of  the  Montana  Copper 
Mining  Company  reveal  no  harmful  amounts  of  'alkali.  The  soil 
is  merely  water-logged.  The  district  southwest  of  Fresno  City, 
California,  is  a  good  example  of  the  second  class.  Here  the 
ground-water  level  has  risen  in  places  to  a  height  of  over  60 
feet  as  a  result  of  the  inflow  of  seepage  water  from  irrigated 
lands  and  leaky  ditches.  The  rise  of  the  water  table  near  the 
surface  and  the  dissolving  of  mineral  salts  by  it  has  accumulated 
so  much  alkali  near  the  surface  and  to  render  much  of  the  land 
unfit  for  the  more  profitable  crops,  such  as  raisin  grapes  and 
deciduous  fruit  trees  (Drainage  of  Irrigated  Lands  in  the  San 
Joaquin  Valley,  O.  E.  S.,  Bui.  217).  Much  of  the  low-lying  land 
bordering  on  Great  Salt  Lake  is  an  example  of  the  third  class. 
Here  virgin  soil  is  so  impregnated  with  common  salt  and  other 
minerals  as  to  be  non-productive  until  the  greater  part  of  such 
salts  have  been  removed  by  copious  irrigations  and  underground 
drainage. 

NEED  FOR  DRAINAGE. — Some  engineers  have  gone  so  far  as 
to  advocate  that  all  irrigated  lands  be  provided  with  drainage 
systems.  Since  only  a  relatively  small  part  of  such  lands  re- 
quire drainage  it  is  manifestly  unjust  to  impose  so  heavy  a 
burden  upon  all  farmers  under  irrigation  enterprises.  A  better 
plan  is  to  prevent,  so  far  as  practicable,  the  water-logging  of 
ia\v  lands  and  the  rise  of  the  alkali  by  a  skillful  use  of  water  and 
by  keeping  the  natural  drainage  channels  open.  In  spite  of  all 
that  can  be  done,  however,  in  the  way  of  preventative  measures, 
a  certain  percentage  of  irrigated  lands  is  certain  to  become  in- 


168  USE  OF  WATER  IN  IRRIGATION 

juriously  affected  by  too  much  water,  too  much  alkali,  or  both. 
Such  tracts  should  receive  early  consideration  in  order  that  the 
proper  remedy  may  be  applied  before  valuable  crops  are  de- 
stroyed and  the  soil  rendered  unproductive.  The  rise  of  the 
water  table  can  be  readily  observed  by  the  use  of  small  test 
wells.  The  water  in  these  wells  can  be  analyzed  to  determine 
the  kind  and  amount  of  mineral  salts  which  it  holds  in  solution. 
The  height  to  which  soil  water  may  rise  without  injury  to  crops, 
varies  with  the  seasons,  crops  and  other  conditions,  but  generally 
speaking,  4  feet  below  the  surface  is  looked  upon  as  the  danger 
line. 

In  preparing  the  following  paragraphs  which  aim  to  present 
an  outline  of  the  best  drainage  practice  of  the  West,  the  writer 
desires  to  acknowledge  his  indebtedness  to  R.  A.  Hart  super- 
vising drainage  engineer  of  the  O.  E.  S.,  U.  S.  D.  A. 

KIND  OF  DRAINS. — Covered  drainage  systems  should  be  used 
for  farm  work  as  they  are  most  efficient  and  more  economical 
in  the  long  run.  Clay  tile,  cement  tile  or  lumber-box  conduits 
may  be  employed.  Clay  tile  are  to  be  preferred.  They  should 
be  hard-burned  but  not  brittle,  of  good  shape  and  condition, 
free  from  blisters  and  serious  cracks  and  have  walls  as  im- 
pervious as  possible  and  strong  enough  to  bear  the  necessary 
weight  of  earth.  Cement  tile  should  only  be  used  when  clay  tile 
is  not  available  at  reasonable  rates.  It  should  be  machine-made, 
mixed  wet,  of  proportions  about  2 : 1  and  should  be  steam-cured. 
Lumber-box  conduits  should  invariably  be  supplied  with  bottoms 
and  should  be  so  constructed  that  their  integrity  of  form  will  not 
depend  on  the  nailing,  since  nails  are  soon  destroyed  by  the 
salts.  This  may  be  accomplished  by  cutting  shoulders  in  the 
tops  and  bottoms  for  holding  the  sides  apart. 

DEPTH  OF  DRAINS. — Drains  in  an  irrigated  district  should  not 
be  laid  less  than  6  feet  in  depth,  save  in  exceptional  cases  where 
a  thick  impervious  stratum  is  encountered  at  a  less  depth. 
Drains  having  a  depth  of  8  feet  or  more  are  much  more  ef- 
fective, as  a  rule,  but  the  additional  cost  of  installing  them  is  often 
prohibitive. 

LOCATION  OF  DRAINS. — As  a  general  thing  drains  should  be 
located  near  the  upper  edge  of  water-logged  areas  or  belts,  but 
if  the  subsoil  is  coarse  gravel  it  is  preferable  to  locate  the  lines 


WASTE,  MEASUREMENT,  AND  DELIVERY      169 

in  the  lower  parts  and  depressions.  If  considerable  areas  of 
comparatively  level  land,  having  fairly  uniform  soil  conditions  are 
to  be  drained,  the  lines  may  be  located  with  some  regularity  from 
200  to  500  feet  apart,  depending  on  the  nature  of  the  soil.  Where 
conditions  are  irregular  no  rule  for  proximity  of  drains  can  be 
given  except  to  state  that  the  lines  must  be  located  so  as  to  inter- 
cept the  waste  water  along  the  line  of  its  entrance  to  the  field, 
which  is  usually  at  the  foot  of  a  change  in  slope  from  a  steep  to  a 
lighter  grade. 


FIG.  60. — Plan  and  part  elevation  of  drainage  system,  showing  intercepting 

drains. 

RELIEF  WELLS. — In  many  cases,  however,  the  seepage  water 
comes  from  deep  sources  and  is  under  pressure.  Obviously 
there  is  a  limit  at  which  drains  can  be  laid  economically,  but 
fortunately  the  seepage  may  be  intercepted  by  means  of  relief 
wells  so  located  as  to  connect  the  water-bearing  stratum  with  a 
drain  at  ordinary  depth.  Fig.  60  shows  the  plan  and  part  eleva- 
tion of  a  drainage  system  so  constructed  as  to  intercept  seepage 
from  two  distinct  sources.  The  drain  line  cuts  off  the  seepage 
from  the  upper  stratum  directly,  while  the  relief  wells  convey 
the  pressure  water  from  the  lower  stratum  to  the  drain.  These 
wells  may  be  bored  with  a  post  hole  auger  and  should  be  cased  or 
filled  with  coarse  gravel. 


170 


USE  OF  WATER  IN  IRRIGATION 


REQUIRED  CAPACITY. — It  is  difficult  to  give  general  rules  re- 
garding necessary  capacity  for  drainage  systems,  but  it  is  usually 
safe  to  provide  a  capacity  of  one-fifth  the  irrigation  supply  for 
lands  having  a  clay  subsoil  and  a  capacity  of  one-half  the  irri- 
gation supply  for  lands  having  a  sandy  subsoil.  If  the  subsoil 
is  coarse  gravel  it  is  necessary  to  determine  the  contributing  area 
instead  of  the  injured  area  and  to  provide  a  capacity  of  about 
one-half  the  irrigation  supply  of  the  area  directly  contributing. 

GRADE. — The  carrying  capacity  of  a  tile  of  given  diameter 
•depends  mainly  on  the  fall  of  the  drain.  The  smaller  the  drain 
the  more  grade  is  required.  For  the  smaller  sizes  a  fall  of  at  least 


\         \\\\\A       \         I  L 


Road 

Surface  Contour 100 — 

Drain.  


Contour .— 100—  Relief  Well 


FIG.  61. — A  common  system  of  drainage  as  applied  to  an  irrigated  farm. 

1  foot  per  thousand  is  required  but  where  conditions  permit 

2  or  more  feet  per  thousand  are  preferable.     For  the  larger  sizes 
the  fall  should  be  at  least  a  half-foot  per  thousand  and  where 
the  necessary  fall  can  be  had  double  or  even  treble  this  grade 
may  be   advantageously  adopted.     Tile   should   be   laid   on  a 
uniform  grade  so  far  as  possible  and  in  straight  lines  (Fig.  61). 

SIZE  OF  TILE. — It  is  not  economical  to  use  tile  smaller  than  6 
inches  in  diameter  and  the  use  of  tile  less  than  4  inches  is  not 
to  be  thought  of.  On  the  other  hand  it  is  rarely  necessary  to 
use  tile  larger  than  12  inches  in  diameter  for  farm  drainage. 
The  latter  size  will  take  care  of  about  a  mile  of  drainage  in  gravel 
when  laid  on  a  grade  of  1  foot  per  thousand.  Nothing  smaller 


WASTE,  MEASUREMENT,  AND  DELIVERY      171 

than  an  8-inch  tile  should  be  laid  in  gravel  and  nothing  smaller 
than  a  li-inrh  tile  in  sand.  A  12-inch  tile  will  take  care  of 
the  drainage  developed  by  a  system  of  10  miles  of  laterals  laid 
in  a  clay  subsoil  and  of  about  4  miles  laid  in  a  sand  subsoil,  on 
the  above-named  grade.  As  a  general  rule  it  may  be  stated  that 
a  given  size  of  tile,  up  to  12  inches  will  carry  as  much  water 
on  the  same  grade  as  two  lines  of  the  next  smaller  size. 

METHODS  OF  INSTALLATION. — The  use  of  machinery  for  exca- 
vating is  advisable  whenever  possible  but  ordinarily  it  will  be 
found  necessary  to  resort  to  hand  labor.  Owing  to  the  fluxible 
nature  of  irrigated  soils,  it  is  generally  found  expedient  to  employ 
a  small  gang  of  men  on  each  line  and  to  complete  the  work  in 
short  sections,  keeping  the  trenchers  as  close  together  as  possible. 
Work  must  always  commence  at  the  outlet  of  each  line  and  pro- 
ceed up  the  slope  so  the  developed  water  will  readily  drain  away. 
The  trench  should  not  be  opened  ahead  of  the  work,  even  to  a 
shallow  depth,  and  it  is  a  fatal  mistake  to  plow  or  scrape  a  trench 
in  advance  of  the  diggers.  The  trench  should  be  cut  from  surface 
to  grade  as  rapidly  as  possible  and  immediately  thereafter  the 
tile  laid  and  blinded  with  a  few  inches  of  earth  caved  from  the 
edges  of  the  trench.  By  systematic,  rapid  trenching  it  is  usually 
possible  to  proceed  without  much  difficulty  and  at  a  reasonable 

(cost  but  if,  in  spite  of  all  precautions,  caving  in  takes  place,  it 
will  be  necessary  to  brace  the  trench  by  means  of  long  planks 
and  short  cross-pieces  or  sewer  braces,  and  in  special  cases  to 
sheet  the  trench  tightly.  These  operations,  of  course,  increase 
the  cost  greatly  and  should  only  be  resorted  to  when  all  other 
measures  fail.  The  best  way  to  avoid  difficulty  is  to  choose  the 
season  of  lowest  ground- water  table  and  to  avoid  storm  periods. 
Irrigation  water  should  be  kept  off  the  field  that  is  being  drained 
and  also  from  higher  and  adjacent  fields  if  possible. 

The  tile  should  be  laid  carefully,  end  to  end,  in  a  straight  line 
and  on  an  even  grade.  It  is  not  necessary  to  separate  the  tile 
in  any  soil  but  in  sandy  or  silty  soils  it  may  be  necessary  to  pro- 
tect the  joints  against  the  entrance  of  material.  Burlap  or 
cheesecloth  doubled  several  times  makes  an  effective  filter.  If 
gravel  is  available  it  is  well  to  pack  a  quantity  of  graded  material 
ranging  from  coarse  sand  to  stones  an  inch  in  diameter  about  the 
joints,  placing  the  coarser  material  next  to  the  tile.  The  tile 


172  USE  OF  WATER  IN  IRRIGATION 

should  be  blinded  immediately,  to  prevent  subsequent  displace- 
ment in  case  of  caving.  If  the  material  is  very  soft,  it  is  advisable 
to  lay  boards  under  the  tile  to  keep  it  in  position  and  if  it  is 
impossible  to  keep  sediment  out  of  the  line  during  construction 
it  is  well  to  operate  sewer  rods  from  openings  in  the  line  down  the 
slope  from  the  point  where  tile  is  being  laid.  It  is  also  advisable 
to  turn  a  stream  of  irrigation  water  into  the  upper  end  of  each 
line  for  some  time  when  the  system  is  complete,  in  order  to 
flush  out  sediment.  Flushing  should  be  resorted  to  if  sediment 
makes  its  way  into  the  drains  at  later  periods.  Almost  any 
drain  will  be  improved  by  occasional  flushings. 

BACKFILLING. — Actual  backfilling  should  be  done  after  the  tile 
laying  is  complete  and  there  is  no  better  way  of  accomplishing  this 
than  by  the  use  of  a  plow  attached  to  a  long  pole  evener,  drawn 
by  three  or  more  horses.  The  spoil  should  be  ridged  up  over  the 
trench  to  allow  for  subsequent  settling.  Irrigation  should  not 
be  applied  directly  over  the  completed  trenches  and  canals  and 
ditches  should  be  carried  across  them  in  flumes. 

MANHOLES. — Manholes  in  a  drainage  system  serve  several 
useful  purposes.  They  offer  an  opportunity  for  observation  of 
the  flow  of  water  and  for  access  to  the  drain  in  case  it  becomes 
inoperative,  so  that  cleaning  devices  may  be  easily  inserted. 
Also  by  extending  the  manhole  a  foot  or  more  below  the  tile 
level  a  basin  is  formed  in  which  sediment  may  be  trapped  and 
removed  from  time  to  time.  In  soils  that  may  be  expected  to 
enter  the  drains  when  wet,  manholes  should  be  installed  at  all 
junctions,  changes  in  direction  or  slope  and  at  intervals  of 
not  to  exceed  500  feet  on  straight  lines.  In  gravelly  or 
compact  soils  they  may  well  be  eliminated.  For  observation 
purposes  only  nothing  is  better  than  a  standpipe  of  12-inch  tile 
topped  with  a  length  of  sewer  pipe,  provided  with  a  cap.  The 
bottom  tile  should  have  holes  cut  for  the  drain  a  foot  above  the 
bottom  of  the  tile  and  gravel  should  be  placed  on  the  bottom. 

COST. — On  account  of  the  varying  soil  conditions,  effectiveness 
of  drains  and  materials,  and  methods  employed  it  is  impossible 
to  estimate  with  accuracy  the  cost  of  drainage  of  a  given  tract 
without  making  a  special  study  of  that  tract.  A  summary  of 
the  experience  that  has  been  gained,  however,  warrants  the 
fixing  of  certain  limits  of  probable  cost. 


WASTE,  MEASUREMENT,  AND  DELIVERY      173 

Outlet  drainage  systems  cost  from  $3  to  $15  per  acre  and  often 
accomplish  n  great  deal  of  farm  drainage  directly.  At  the  latter 
figure,  very  lit.tle  tile  drainage  should  be  necessary.  Farm  drain- 
age, when  single  tracts  or  a  collection  of  small  units  are  handled, 
and  the  soil  is  stable,  varies  in  cost  from  $10  per  acre  to  $20  per 
acre  with  the  average  close  to  $14  per  acre.  If  the  soil  is  fluxible. 
however,  or  the  material  is  so  hard  as  to  require  picking,  the  costs 
run  from  $20  to  $50  per  acre  and  if  the  trenching  work  must  be 
protected  by  sheeting  the  cost  is  often  considerably  more. 

The  cost  of  clay  tile  in  the  irrigated  sections  averages  from 
about  a  cent  per  inch  of  inside  diameter  per  foot  of  length  in  the 
smallest  size  up  to  2  cents  per  inch  of  inside  diameter  per  foot 
of  length  in  the  largest  size  ordinarily  used.  Trenching,  laying 
tile  and  backfilling  by  hand  in  stable  soil  to  an  average  depth  of 
6  feet,  varies  from  7  cents  to  15  cents  per  foot.  If  the  material 
is  hard  or  unstable  the  cost  will  run  up  to  25  cents  per  foot  and 
if  sheeting  is  required  the  cost  will  be  more  than  double  this 
figure.  Machine  trenching  is  ordinarily  much  cheaper  and  5-foot 
trenching  has  been  contracted  at  about  4  cents  per  foot. 


CHAPTER  VI 
IRRIGATION  OF  STAPLE  CROPS 

35.  Alfalfa  and  Other  Forage  Crops. — Of  the  crops  reported 
in  the  17  Western  States  by  the  Census  of  1910,  30.6  per  cent,  was 
in  alfalfa,  21.1  per  cent,  in  wild,  salt,  or  prairie  grasses,  and  11.2 
per  cent,  in  other  forage  crops.  These  returns  convey  some 
idea  of  the  importance  of  alfalfa  and  the  preponderance  of  forage 
crops  in  western  farming.  The  value  of  alfalfa  to  the  West  is 
more  than  double  that  of  all  other  forage  crops  combined  and  as 
indicated  by  the  incomplete  returns  of  the  census  probably  ex- 
ceeds $80,000,000  a  year. 

Notwithstanding  its  importance  and  value  in  irrigation  farm- 
ing, the  profits  on  the  area  devoted  to  this  crop  can  be  greatly 
increased  if  more  care  and  skill  are  exercised  in  growing  it. 
The  western  irrigator  has  seldom  been  able  financially  to  prepare 
his  fields  in  such  a  way  as  to  insure  the  most  efficient  irrigation 
and  the  highest  profits.  In  consequence  valuable  water  is  waste- 
fully  applied  to  land  that  is  in  no  fit  condition  to  be  irrigated. 
On  the  large  acreage  in  irrigated  alfalfa  this  amounts  to  an 
enormous  loss.  This  is  shown  in  the  case  of  southern  Idaho. 
There  soil,  water,  climate  and  other  conditions  are  unexcelled 
for  the  production  of  heavy  yields  of  alfalfa  and  under  good  farm- 
ing seasonal  yields  of  6  to  8  tons  per  acre  can  be  harvested,  yet 
the  general  average  seasonal  yield  per  acre  in  1910  was  only 
3.26  tons. 

LANDS  ADAPTED  TO  ALFALFA.  1 — The  most  essential  conditions 
for  the  production  of  alfalfa  are  abundant  sunshine,  a  high 
summer  temperature,  plenty  of  moisture  and  a  large,  deep,  well- 
drained  soil.  All  of  these  essentials  save  moisture  exist  naturally 
in  the  arid  region  of  the  United  States  and  when  water  is  applied 
it  makes  conditions  ideal.  Over  half  a  century  of  experience  has 

'See  Farmers'  Bui.  263  and  373,  U.  S.  D.  A.,  by  the  author. 

174 


IRRIGATION  OF  STAPLE  CROPS  175 

shown  that  alfalfa  can  be  successfully  grown  under  a  wide  variety 
of  soils  and  climate  yet  all  western  lands  are  not  equally  well 
adapted  to  its  growth.  For  this  reason  those  who  are  seeking 
such  lands  with  a  view  to  their  purchase  should  first  make  a 
careful  examination  of  the  character  and  depth  of  soil,  its  be- 
havior when  irrigated,  the  slope  and  evenness  of  the  surface,  the 
presence  of  injurious  salts  and  the  facilities  for  drainage. 

PREPARATORY  CROPS. — Experience  has  shown  that  it  is  diffi- 
cult in  the  course  of  6  months  or  a  year  to  secure  a  good  stand 
of  alfalfa  on  raw  land  that  has  been  covered  by  a  desert  growth. 
This  is  true  particularly  of  rough,  uneven  land  on  which  crop 
rotation  is  not  practised.  It  is  likewise  true  of  land  thickly 
covered  with  brush.  It  has  been  found  impracticable  in  most 
localities  to  secure  a  smooth,  well-graded  surface  where  fresh 
roots  interfere  with  the  proper  use  of  all  grading  and  leveling 
implements.  The  same  is  true  of  hog-wallow  land,  where  con- 
siderable soil  has  to  be  removed  from  the  high  places  and  de- 
posited in  the  low  places.  It  takes  time  and  a  second  preparation 
of  the  surface  before  fields  of  this  character  can  be  put  in  good 
condition  for  the  growth  and  irrigation  of  alfalfa.  If  crop  rota- 
tion .is  to  be  followed  the  necessity  for  a  preparatory  crop  is  not 
so  urgent,  since  the  alfalfa  will  soon  be  plowed  under  to  give  place 
to  another  crop.  In  northern  Colorado,  where  alfalfa  usually 
follows  either  potatoes  or  sugar  beets,  the  surface  is  not 
plowed,  but  merely  harrowed  or  disked  in  the  spring  just  before 
seeding.  If  the  surface  is  uneven  it  is  smoothed  and  leveled  by 
means  of  a  float  or  drag  before  the  seed  is  put  in.  In  south- 
western Kansas  it  is  likewise  considered  best  to  plant  alfalfa  after 
some  cultivated  crop  which  has  held  the  weeds  in  check.  The 
land  is  plowed  in  the  fall  to  a  depth  of  6  inches,  double- disked  in 
the  spring  after  the  weeds  have  started,  and  is  subsequently 
harrowed.  In  the  vicinity  of  Los  Banos,  California,  new  land  is 
almost  invariably  sown  to  barley  or  corn  for  two  seasons  before 
seeding  to  alfalfa.  In  Utah  wheat  or  oats  is  preferred  as  a  pre- 
paratory crop.  The  chief  purpose  of  all  such  preparatory  grain 
crops  is  to  allow  fresh  roots  of  the  original  plant  covering  to  de- 
cay, filled-in  spots  to  settle,  high  places  denuded  of  the  upper 
layer  of  soil  to  weather,  and  in  general  to  prepare  a  well-pulverized 
seed  bed  in  a  smooth,  well-graded  field. 


176  USE  OF  WATER  IN  IRRIGATION 

SEEDING  ALFALFA. — In  northern  Colorado  rotation  of  crops  is 
practised  and  alfalfa  seed  is  sown  with  a  nurse  crop,  usually 
wheat  or  barley.  The  seed  is  drilled  early  in  the  spring  with  a 
common  force-feed  press  drill  equipped  with  an  auxiliary  seed 
box  for  alfalfa  seed  which  is  scattered  broadcast  between  the 
rows  and  covered  by  the  disk  wheels  of  the  press  drill.  From  12 
to  20  pounds  of  alfalfa  seed  are  sown  to  the  acre. 

In  Yuma  and  other  valleys  of  Arizona  October  planting  is 
preferred.  Frequently  in  this  dry  climate  the  land  is  irri- 
gated before  seeding.  It  is  then  cultivated,  seeded  and  harrowed. 

In  the  Sacramento  Valley  of  California,  alfalfa  is  seeded 
generally  in  the  spring  from  February  15  to  April  15.  In  the 
San  Joaquin  valley  the  time  of  seeding  extends  from  March  or 
earlier  to  April.  The  amount  of  seed  used  per  acre  in  both  val- 
leys averages  about  16  pounds. 

The  alfalfa  growers  of  Montana  are  about  equally  divided 
in  opinion  as  to  the  advantages  of  using  a  nurse  crop.  Those 
who  seed  grain  with  alfalfa  claim  that  they  get  more  out  of  the 
land  the  first  season.  Those  who  are  opposed  to  this  practice 
believe  that  the  injury  done  to  the  alfalfa  plants  by  the  grain 
crop  extends  through  several  years  and  that  the  small  gain  of 
the  first  year  is  more  than  offset  by  the  lessened  yields  of  alfalfa 
in  subsequent  years.  Mr.  I.  D.  O'Donnell,  one  of  the  most 
successful  alfalfa  growers  and  feeders  in  the  state  is  an  advocate 
of  the  last-named  practice. 

The  last  >half  of  August  is  the  best  time  to  seed  alfalfa  in 
the  humid  region.  The  soil  is  first  plowed  and  heavily  fertilized 
and  early  in  the  spring  a  hoed  crop,  preferably  potatoes  is 
planted.  When  this  crop  is  harvested  and  the  soil  again  properly 
prepared  it  is  in  excellent  condition  for  alfalfa  seed.  The  long 
growing  season  of  the  middle  and  south  Atlantic  states  en- 
ables the  plant  to  establish  itself  before  the  first  killing  frost. 
In  seeding  alfalfa  in  the  humid  region  it  is  not  safe  to  use  less 
than  20  pounds  to  the  acre. 

ALFALFA  AS  A  BASE  OF  ROTATION. — The  benefits  to  be  derived 
by  rotating  alfalfa  with  irrigated  crops  are  now  quite  generally 
recognized  and  this  practice  is  being  followed  by  the  more  pro- 
gressive communities  of  the  irrigated  region.  Formerly  when 
hay  and  grain  crops  comprised  the  bulk  of  the  western  soil 


IRRIGATION  OF  STAPLE  CROPS  177 

production,  farmers  were  loathe  to  plow  under  a  good  stand  of 
alfalfa  because  it  was  their  best  paying  crop.  In  later  years  the 
raising  of  beets,  potatoes,  small  fruits  and  truck  have  well  nigh 
forced  growers  to  rotate  with  legumes  in  order  to  maintain  the 
fertility  and  good  tilth  of  the  soil. 

On  account  of  the  slow  growth  of  alfalfa  during  the  first 
4  to  6  months  after  seeding  and  the  long  period  required  to 
reach  full  maturity  it  is  not  adapted  to  short  time  rotations 
such  as  is  practised  so  successfully  in  the  more  elevated  and 
cooler  portions  of  the  irrigated  West  where  red  clover  is  sown 
with  grain  in  the  spring  and  in  less  than  18  months  is  plowed 
under.  This  simple  rotation  of  grain  sown  with  clover  one 
season  and  clover  alone  the  next  year,  giving  large  returns 
of  both  grain  and  hay  could  not  well  be  followed  with  alfalfa 
for  the  reason  named  and  for  the  additional  reason  that  it  re- 
quires at  least  3  years  for  the  roots  of  alfalfa  to  develop  fully. 
So  the  most  common  alfalfa  rotation  in  the  West  is  3  to  4  years 
in  alfalfa,  followed  by  root  crops  and  a  nurse  crop  of  grain.  If 
root  crops  are  the  most  profitable  the  tendency  is  to  grow  them 
until  the  yields  and  profits  fall  off  when  the  land  is  again  restored 
by  seeding  to  grain  and  alfalfa. 

INFLUENCE  OF  IRRIGATION  IN  ROOT  DEVELOPMENT. — To  de- 
velop a  good  tap  root  in  the  early  stages  of  growth  of  alfalfa  is 
desirable  for  many  reasons.  It  enlarges  the  feeding  ground -of 
the  plant  and  thus  renders  it  more  vigorous  and  a  heavy  yielder. 
It  guards  it  from  the  bad  effects  of  alternate  dry  and  saturated 
surface  soil  by  drawing  moisture  from  beneath  and  it  prolongs 
the  life  and  usefulness  of  the  plants  by  maintaining  its  most  es- 
sential member  in  a  healthy,  normal  condition. 

When  the  top  layer  of  soil  is  rich  and  kept  continuously 
moist,  alfalfa  plants  seem  to  put  forth  little  effort  to  extend 
their  tap  roots  far  below  the  surface.  The  result  is  a  division 
of  the  main  root  into  several  branches  which  spread  out  and 
become  bushy. 

To  bring  about  deep  rooting,  the  subsoil  should  be  well  drained. 
If  water  and  worse  still,  water  containing  harmful  quantities 
of  salts,  is  allowed  to  rise  into  the  feeding  zone  it  will  injure  and 
in  time  destroy  the  tap  root.  The  presence  of  hardpan  or 

any  formation  which  hinders  root  penetration  likewise  forces 
12 


178  USE  OF  WATER  IN  IRRIGATION 

shallow  rooting.  The  remedy  for  this  condition  is  deep  plow- 
ing, subsoiling  or  else  dynamiting.  But  even  in  well-drained, 
deep  and  thoroughly  cultivated  soils  some  incentive  to  deep 
rooting  is  necessary.  This  can  readily  be  brought  about  by  ap- 
plying to  the  soil  a  scanty  amount  of  water  when  the  plant  is 
young.  At  this  stage  it  should  suffer  for  water  and  this  lack 
of  moisture  will  tend  to  make  it  strike  down  through  its  tap 
root  in  quest  of  more.  It  is  also  a  good  plan  to  apply  water 
some  time  before  seeding  if  the  soil  is  too  dry. 

Perhaps  the  greatest  objections  to  sowing  alfalfa  with  a 
nurse  crop  arises  from  the  injury  done  to  the  root  develop- 
ment of  the  alfalfa.  In  such  a  practice  the  fodder  crop  is  over- 
looked in  an  effort  to  produce  a  good  cereal  crop.  The  latter 
requires  water  early  on  account  of  its  quick-maturing  properties 
and  being  shallow-rooted  it  requires  a  moist  surface  soil.  Both 
are  likely  to  affect  injuriously  the  proper  development  of  the 
roots  of  the  alfalfa. 

THE  IRRIGATION  OF  ALFALFA,  (a)  By  Flooding. — In  the  states 
of  Colorado,  Wyoming,  Montana,  and  Utah  and  to  some  ex- 
tent in  all  Western  States,  flooding,  as  it  is  termed,  from  field 
ditches  and  laterals  is  the  most  common  method  of  irrigating 
hay  and  grain  crops.  As  a  rule  a  medium  head  of  water  is 
used.  This  is  conducted  through  the  supply  ditch  to  the  high- 
est point  of  the  field  and  is  then  divided  into  smaller  heads  and 
distributed  among  the  farm  ditches  and  laterals.  From  these 
in  turn  it  is  made  to  flow  over  the  surface  of  the  land,  all  ex- 
cess water  being  collected  by  the  lower  laterals.  The  temporary 
field  ditches  are  made  to  fit  into  the  natural  slope  and  con- 
figuration of  the  tract  to  be  watered  so  as  to  conduct  the  water 
to  the  high  places. 

This  method  is  well  adapted  to  the  varying  slopes  and  ir- 
regular surface  formation  so  common  in  the  Mountain  States. 
Fields  which  slope  from  5  to  500  feet  per  mile  can  be  success- 
fully watered  in  this  way.  Besides  the  preparation  of  the  land 
is  easy  and  cheap  since  little  change  is  made  in  the  natural  sur- 
face. On  the  other  hand  the  labor  required  to  irrigate  is  ex- 
cessive and  of  the  most  fatiguing  kind. 

The  manner  in  which  forage  crops  are  irrigated  by  flooding 
can  best  be  shown  by  outlining  the  practice  in  a  few  localities. 


IRRIGATION  OF  STAPLE  CROPS  179 

In  northern  Colorado,  for  example,  the  head  used  varies  from 
2  to  4  second-feet  and  is  divided  into  two  or  three  laterals. 
Canvas  or  coarse  manure  dams  are  used  to  check  the  water 
in  the  laterals  and  to  force  it  out  over  the  banks  and  down  the 
slopes  of  the  fields.  In  less  than  3  hours  the  upper  foot  of 
soil  is  usually  thoroughly  moistened.  To  apply  one  watering  in 
this  way  costs  from  15  to  30  cents  per  acre. 

In  Montana  the  field  ditches  are  laid  out  across  the  slope 
on  a  grade  of  1/2  to  3/4  inch  to  the  rod  or  else  down  the 
steepest  slope.  In  the  first  case  the  ditches  are  spaced  50 
to  100  feet  apart  and  water  flows  through  openings  in  the 
bank  made  with  the  shovel  and  spreading  out  covers  a  wide 
space  before  reaching  the  next  lower  ditch.  Each  ditch  carries 
from  40  to  80  miner's  inches  (1  to  2  second-feet)  and  one  man  can 
handle  from  80  to  200  miner's  inches  in  two  or  more  ditches. 
The  canvas  dam  is  the  most  commonly  used  to  check  the  flow 
in  the  ditch  but  earth  and  manure  dams  are  also  common.  The 
earth  is  taken  from  the  low  side  and  when  the  dam  is  broken 
the  hole  is  again  partially  filled  with  the  same  material.  In 
making  use  of  coarse  manure  for  this  purpose  it  is  hauled  by 
teams  and  distributed  in  small  heaps  along  the  ditch  bank  at  in- 
tervals of  30  to  60  feet.  Before  irrigation  begins  it  is  placed 
in  the  ditch  with  a  thin  covering  of  earth  over  its  upper  face. 
The  same  manure  can  be  used  for  several  irrigations. 

In  other  districts  of  Montana  the  field  ditches  are  parallel 
and  extend  down  the  steepest  slope  from  the  supply  ditch  to 
the  catch  ditch  at  the  bottom  of  the  field.  In  this  practice 
the  check  dams  previously  described  are  used.  The  laterals 
are  made  with  a  lister  attached  to  a  sulky  frame,  Fig.  62. 

In  Utah  the  head  varies  from  less  than  1  second-foot  to 
as  high  as  5  second-feet.  During  the  spring  months  when 
the  streams  are  running  bank  full,  large  irrigating  heads  are 
the  rule  but  as  the  stream  flow  diminishes  the  quantities  used 
by  the  farmers  likewise  diminish.  In  this  State,  the  farms,  as 
well  as  the  alfalfa  fields,  are  smaller  than  those  of  neighboring 
states.  One  also  finds  more  permanent  ditches  and  turnout 
boxes. 

(b)  By  Borders. — The  borders  or  lands  described  under 
Art.  20  are  used  extensively  for  the  irrigation  of  alfalfa.  When 


180 


USE  OF  WATER  IN  IRRIGATION 


an  alfalfa  field  is  divided  off  into  borders  it  can  be  watered 
at  a  low  cost  per  acre  and  with  little  labor.  It  is  therefore  a 
paying  investment  to  prepare  the  surface  for  this  kind  of  ap- 
plication rather  than  for  flooding  whenever  conditions  are 
suitable.  It  calls  for  a  fairly  smooth,  uniform  slope  of  5  to  20 
feet  per  mile  for  any  available  supply  of  water  of  2  to  10  second- 
feet.  As  a  rule  the  borders  or  lands  are  too  long.  One  is  seldom 
justified  in  exceeding  900  feet  between  head  ditches.  On  more 
uneven  slopes  a  much  shorter  run  is  desirable.  Several  second- 
feet  aie  turned  into  each  border  and  the  number  of  strips  which 
can  be  watered  simultaneously  depends  on  the  quantity  of  water 
available  in  the  supply  ditch.  Immediately  after  a  crop  has 
been  cut  and  removed  a  thin  sheet  of  water  will  flow  over  the 


FIG.  62. — Lateral  ditch  plow. 

stubble  and  down  the  border  in  a  short  time  without  backing 
up.  Irrigation  at  this  stage  does  not,  therefore,  require  high 
border  levees.  On  the  contrary,  due  to  the  obstruction  to  the 
flow  of  water  caused  by  the  larger  growth,  the  time  required  to 
irrigate  a  fairly  well  matured  crop  is  much  longer  and  the  side 
levees  require  to  be  higher  to  prevent  over-topping. 

The  most  common  size  of  borders  in  the  Salt  River  valley 
of  Arizona  is  66  feet  wide  and  1320  feet  long.  A  head  of  300 
miner's  inches  (7  1/2  second-feet)  is  turned  into  four  borders. 
The  time  required  to  irrigate  each  set  of  four  borders  averages 
about  6  hours  and  the  amount  of  water  applied  at  a  time  varies 
from  2  to  4  acre-inches  per  acre.  This  water,  however,  is  seldom 
evenly  distributed  throughout  the  length  of  the  border.  The 


IRRIGATION  OF  STAPLE  CROPS  181 

soil  in  the  upper  end  may  be  moistened  to  a  depth  of  30  inches, 
that  of  the  middle  to  a  depth  of  27  inches,  while  that  near  the 
lower  end  of  the  border  may  not  be  moistened  to  a  greater  depth 
than  15  inches. 

(c)  By  Checks. — With  a  large  volume  in  the  feed  ditch  and 
a  light  sandy  soil  on  a  flat  slope,  alfalfa  can  be  watered  in  checks 
at  a  low  cost  per  acre  for  the  season.     In  the  Modesto  and 
Turlock  Irrigation  districts  of  central  California  the  feed  ditches 
are  designed  to  carry  10  to  20  second-feet.     These  large  heads 
are  used  by  the  farmers  in  turn  for  short  periods  of  time.     Five 
second-feet   flowing  on  a  check  containing  1  acre  would  cover 
it  to  a  depth  of  5  inches  in  1  hour.     If  a  head  of  15  second- 
feet  is  available,  three  checks  can  be  irrigated  simultaneously. 
Irrigation  begins  with  the  higher  checks  and  works  down. 

On  the  west  side  of  the  .San  Joaquin  river  under  the  Miller 
and  Lux  canal  system,  the  check  levees  follow  contour  lines  and 
enclose  areas  of  1  to  3  acres.  The  average  head  used 
is  8  1/2  second-feet  and  the  time  required  to  irrigate  an  acre 
varies  from  1/2  to  1  hour  and  over.  The  checks  and 
ditches  under  this  system  are  not  so  well  provided  with  boxes  and 
gates  as  are  those  of  the  Modesto  and  Turlock  districts  and  in  con- 
sequence the  cost  per  acre  for  the  season  is  about  50  cents  higher. 

(d)  By    Furrows. — Alfalfa,    clover    and    other    forage    crops 
grown  in  the  State  of  Washington  and  in  parts  of  Idaho  and  other 
states  are  irrigated  by  the  furrow  method.     Where  the  soil  is 
deep  and  fairly  retentive  of  moisture,  the  furrows  are  spaced  3  1/2 
to  4  feet  apart  but  in  sandy  and  shallow  soil  the  spacing  varies 
from  2  to  2  1/2  feet.     The  length  of  the  furrow  likewise  varies 
with  the  character  of  the  soil.     In  sandy  soil  200  feet  is  considered 
sufficient  whereas  in  the  heavy  and  deeper  soils  it  is  customary 
to  run  water  in  furrows  330  to  660  feet  or  even  longer  distances. 

In  Washington  the  water  is  delivered,  as  a  rule,  in  a  con- 
tinuous stream,  1  second-foot  being  allowed  for  160  acres. 
By  this  custom  the  owner  of  a  small  farm  of  20  acres  receives 
only  one-eighth  of  a  second-foot,  a  flow  altogether  too  small  to 
apply  economically.  This  defect  in  water  contracts  is  partly 
overcome  by  an  exchange  of  water  among  neighbors  who  in  this 
way  adopt  a  voluntary  rotation  system. 

The  head  of  water  available  is  distributed  to  the  furrows 


182  USE  OF  WATER  IN  IRRIGATION 

from  head  ditches  through  lath  or  metal  spouts.  Wooden  flumes 
and  pipes  of  concrete,  wood  and  galvanized  iron  sometimes  take 
the  place  of  head  ditches  in  earth.  A  head  of  half  a  second-foot 
may  be  apportioned  among  50  or  more  furrows  and  permitted 
to  run  from  6  to  12  hours  in  the  lighter  soils  and  from  1  to  3 
days  in  the  heavy  soils.  Alfalfa  is  irrigated  after  each  cutting 
and  occasionally  between  cuttings.  The  quantity  of  water  ap- 
plied at  each  irrigation  is  seldom  less  than  6  acre-inches  per 
acre  but  there  is  always  a  certain  percentage  wasted  by  deep 
percolation. 

(e)  By  Surface  Pipes. — This  method  is  described  in  Art.  19. 

AMOUNT  OF  WATER  REQUIRED. — Alfalfa  requires  more  water 
than  most  crops.  This  is  readily  accounted  for  by  the  character 
of  the  plant,  the  rapidity  with  which  it  grows,  the  number  of 
crops  produced  in  one  season,  and  the  heavy  tonnage  obtained. 

As  a  result  of  careless  practice  there  is  a  lack  of  uniformity  in 
the  quantity  of  water  used,  the  volume  applied  frequently  being 
far  in  excess  of  the  needs  of  the  crop.  The  majority  of  the 
records  collected  and  published  by  the  Office  of  Experiment 
Stations  show  a  yearly  duty  of  water  for  alfalfa  ranging  from 
2.5  to  4.5  feet  in  depth  over  the  surface,  while  in  quite  a  large 
number  of  cases  the  volumes  applied  would  have  covered  the 
area  irrigated  to  depths  of  6  to  15  feet. 

From  the  large  number  of  measurements  made  on  the  duty  of 
water  it  is  possible  to  select  some  that  possess  great  value,  since 
they  indicate  what  can  be  accomplished  with  a  given  quantity  of 
water. 

During  the  season  of  1904  careful  measurements  were  made 
by  C.  E.  Tait  of  the  amount  of  water  used  on  the  alfalfa  fields 
in  the  vicinity  of  Pomona,  Cal.  The  rainfall  at  Pomona  for  the 
winter  of  1903-04  was  much  below  the  normal  and  amounted  to 
about  9.1  inches.  The  quantity  of  irrigation  water  applied 
by  pumping  averaged  2.3  feet  in  depth  and  the  yield  of  cured  hay 
averaged  from  1  to  1.5  tons  per  acre  per  crop,  five  or  six  crops 
being  common.  These  figures  are  corroborated  by  many  others 
collected  in  southern  California.  Perhaps  in  no  other  locality  of 
the  arid  region  is  a  greater  tonnage  of  alfalfa  obtained,  yet  in 
a  climate  of  scanty  rainfall  having  a  long,  dry,  hot  summer  only 
a  comparatively  small  amount  of  water  is  used.  About  a  third 


IRRIGATION  OF  STAPLE  CROPS 


183 


cf  the  9000  acres  irrigated  by  the  Riverside  Water  Company  is 
in  alfalfa  and  for  the  past  7  years  the  average  depth  applied  has 
I MVI i  2.31  feet,  while  the  depth  of  rainfall  and  irrigation  water 
combined  has  averaged  3.18  feet. 

In  1903  the  writer,  then  Director  of  the  Montana  Experi- 
ment Station,  applied  differ- 
ent depths  of  water  to  seven 
plats  of  alfalfa  with  the  results 
given  in  the  following  table. 
It  will  be  seen  that  a  high 
tonnage  for  so  short  a  season 
as  prevails  in  Montana  was 
obtained  from  plat  5  with  the 
use  of  2  feet  of  water.  By  ir- 
rigating plat  6  seven  times, 
and  plat  7  eight  times,  it  was 
possible  to  increase  the  yield 
to  the  amounts  stated.  The 
results  of  this .  experiment 
seem  to  confirm  the  best  prac- 
tice of  southern  California, 
which  may  be  summed  up  by 


Yield  In  Tons  per  Acre 

0  l->  KJ  CO  »-  Ol  OS  -O  OO  «0 

Total  Depth  of  Water  in  Inches 

0 

12 

18 

24 

30 

30 

48 

FIG.  63. — Average  yield  of  alfalfa 
at  Davis,  Cal.,  from  different  quanti- 
ties of  water. 


stating  that  in  localities  hav- 
ing an  annual  rainfall  of  about 
12  inches  remarkably  heavy 
yields  of  alfalfa  may  be  ob- 
tained from  the  use  of  24  to  30  inches  of  irrigation  water,  pro- 
viding it  is  properly  applied. 

TABLE  No.  30 

Quantities  of  Water  Applied  to  Alfalfa  and  Yields  Secured,  Montana 
Experiment  Station 


Plat 
number 

Depth  of 
irrigation, 
feet 

Depth  of 
rainfall, 
feet 

Total 
depth, 
feet 

Yield  per  acre 
of  cured  alfalfa, 
tons 

1 

0.5 

0.70 

1.20 

4.61 

2 

None 

0.70 

0.70 

1.95 

3 

1.0 

0.70 

1.70 

4.42 

4 

1.5 

0.70 

2.20 

3.75 

5 

2.0 

0.70 

2.70 

6.35 

6 

2.5 

0.70 

3.20 

7.20 

7 

:;.() 

0.70 

3.70 

7.68 

184 


USE  OF  WATER  IN  IRRIGATION 


Results  similar  to  the  preceding  were  obtained  at  Davis, 
California  (Bui.  10,  U.  S.  D.  A.)  during  the  years  1910  to 
1912  inclusive.  These  results  are  summarized  in  Table  31 
and  Fig.  63. 

TABLE  No.  31 

Summary  of  Results  of  Alfalfa  Irrigation  Investigations,  1910,  1911,  and 

1912 


Depth 
of 
water 
ap- 
plied 

Yield  in  tons 
per  acre 

Value  of  hay  per 
acre  at  $7  per  ton 

Cost  of  production 

Net  profit  per  acre 

1910 

1911 

1912 

1910 

1911 

1912 

1910 

1911 

1912 

1910 

1911 

1912 

Inches 
0 

3.856.02 

6.52 

$26.95 

$42.1-4 

$38.64 

$8.65 

$13.50 

$12.40 

$18.30 

$28.  64  $26.  24 

12 
18 
24 

4.75 

7.52 

6.51 
7.02 
8.32 

33.25 

52.64 

45.57 
49   14 

13.40 

19.60 

17.35 
19  85 

19.85 

33.04 

28.22 
29.29 
34.14 

6.00 

8.38 

42.00 

58.66 

58.24 

18.90 

24.20 

24.10 

23.10 

34.46 

30 

7.53 

9.61 

9.43 

52.71 

67.27 

66.31 

23.15 

27.85 

27.35 

29.56 

39.42 

38.96 

36 

7.58 

9.33 

9.38 

53.00 

65.31 

65.66 

24.15 

28.05 

28.10 

28.91 

37.26 

37.56 

48 

8.45 

9.64 

8.87 

59.15 

67.48 

62.09 

27.80 

30.25 

28.80 

31.35 

37.23 

33  .  29 

60 

10.04 

70.20 

33  .  65 

36.63 

WINTERKILLING  OF  ALFALFA. — The  winterkilling  of  alfalfa  is 
confined  chiefly  to  the  colder  and  more  elevated  portions  of  the 
Rocky  Mountain  region  and  to  the  northern  belt  of  humid  states. 
Damage  from  cold  is  rare  in  Arizona  and  in  California  it  is  con- 
fined to  young  plants.  In  both  the  Sacramento  and  San  Joaquin 
valleys  of  the  latter  State  the  seed  is  frequently  sown  in  mid- 
winter and  the  slight  frosts  which  occur  occasionally  in  December 
and  January  in  both  these  valleys  are  severe  enough  to  kill  very 
young  plants.  The  belief  is  common  that  the  plants  are  safe 
after  they  have  put  forth  their  third  leaf. 

In  the  colder  portions  of  Montana,  Wyoming,  Colorado,  Utah, 
and  the  Dakotas  alfalfa  is  apparently  winterkilled  from  a 
variety  of  causes  and  sometimes  from  a  combination  of  causes. 
The  percentage  of  loss  around  Greeley,  Colorado,  has  been  placed 
at  2  per  cent,  per  annum.  In  this  locality  and  throughout  the 
Cache  la  Poudre  Valley  in  northern  Colorado  most  of  the  winter- 
killing is  done  in  open,  dry  winters  and  is  quite  generally  at- 
tributed to  a  scarcity  of  moisture  in  the  soil.  In  the  winter 
of  1907  considerable  damage  was  done  to  the  alfalfa  fields  around 
Loveland,  Colorado,  on  account  of  the  long  dry  spell  in  mid- 
winter. The  old  alfalfa  fields  suffered  most.  It  was  the  opinion 


IRRIGATION  OF  STAPLE  CROPS  185 

of  the  farmers  that  a  late  fall  irrigation  would  have  prevented 
the  loss. 

Near  Wheatland,  Wyoming,  the  higher  portions  of  the  fields 
suffer  most  damage  in  winter,  and  here  also  the  cause  is  said 
to  be  lack  of  moisture  in  the  soil,  combined  with  the  effects 
produced  by  cold  and  wind. 

At  Choteau,  in  northern  Montana,  a  farmer  watered  late 
in  the  fall,  part  of  an  alfalfa  field  which  was  2  years  old,  and 
it  winterkilled,  while  the  unwatered  portion  escaped  injury. 
This  and  other  evidence  along  the  same  line  which  might  be  given 
go  far  to  demonstrate  that  under  some  conditions  too  much 
moisture  is  as  detrimental  as  too  little. 

Probably  the  chief  cause  of  the  winterkilling  of  alfalfa  is 
alternate  freezing  and  thawing.  The  damage  from  this  cause  is 
greatly  increased  when  water  is  left  standing  on  the  surface.  A 
blanket  of  snow  is  a  protection,  but  when  a  thin  sheet  of  ice 
forms  over  portions  of  a  field  the  result  is  usually  fatal  to  plants. 
The  bad  effects  of  alternate  freezing  and  thawing  on  alfalfa 
may  be  observed  at  the  edge  of  a  snow  bank.  This  crop  is 
likewise  injured  by  the  rupture  of  the  tap  roots  caused  by  the 
heaving  of  the  soil. 

From  present  knowledge  of  the  subject,  the  means  which 
may  be  used  to  protect  alfalfa  fields  from  winterkilling  may  be 
summed  up  as  follows:  Where  both  the  soil  and  the  air  are  dry 
the  plant  should  be  supplied  with  sufficient  water  for  evapora- 
tion but  the  land  should  be  drained  so  thoroughly  that  none  of 
the  top  soil  is  saturated;  a  late  growth  should  not  be  forced  by 
heavy  irrigations  late  in  the  growing  season;  if  the  soil  is  dry, 
irrigate  after  the  plants  have  stopped  growing;  and  the  latest 
growth  should  be  permitted  to  remain  on  the  ground,  unpastured, 
as  a  protection. 

It  may  be  stated  in  conclusion  that  the  loss  to  the  farmer 
from  the  winterkilling  of  alfalfa  is  not  as  great  as  might  appear 
at  first.  The  damage  is  done  in  winter  and  there  is  ample  time 
to  plow  the  plants  under  and  secure  another  crop,  which  is 
usually  heavy,  owing  to  the  amount  of  fertilizers  added  by 
the  roots  of  alfalfa.  The  Montana  farmer  who  increased  his 
average  yield  of  oats  from  50  to  103  bushels  per  acre  by  plowing 
under  winterkilled  alfalfa  illustrated  this  point. 


186  USE  OF  WATER  IN  IRRIGATION 

36.  Irrigation  of  Grain. — New  irrigation  enterprises  have  been 
settled  for  the  most  part  by  pioneering  people  who  have  but  little 
capital.  To  settlers  of  this  class  the  planting  of  small  grain  crops 
during  the  first  years  of  their  struggles  with  desert  conditions  is  a 
necessity.  Wheat  and  vegetables  constitute  the  staple  food  sup- 
ply for  the  poorer  class,  while  corn,  barley,  oats  and  rye  fur- 
nish food  for  both  man  and  beast.  Such  crops  as  a  rule  require 
the  smallest  outlay  to  prepare  the  land  for  irrigation,  and  bring 
the  quickest  returns.  They  do  fairly  well  on  virgin  soil  and 
by  their  growth  fit  the  raw  land  for  such  crops  as  alfalfa  and 
clover.  They  also  require  water  at  a  time  when  snow-fed 
streams  are  high  and  begin  to  ripen  before  the  water  supply  runs 
low.  For  these  and  other  reasons  which  might  be  named  grain 
crops  will  continue  to  be  of  prime  importance  so  long  as  farmers 
with  limited  means  settle  on  the  newly  reclaimed  lands  of  the 
West.  On  the  other  hand,  the  continuous  cropping  of  grain, 
wheat  in  particular,  should  not  be  regarded  as  good  management 
for  the  irrigated  farm  because  of  the  small  returns.  As  soon 
as  the  land  is  fit  and  the  farmer  is  able  financially  to  prepare 
the  surface  for  more  profitable  crops,  he  should  gradually  con- 
vert the  greater  part  of  his  grain  fields  into  alfalfa,  sugar  beets, 
potatoes,  truck,  and  fruit. 

The  results  of  growing  grain  under  irrigation  in  rotation 
with  other  crops  have  been  carefully  studied  by  W.  W.  Mc- 
Laughlin,  in  charge  of  irrigation  investigations  of  the  Office 
of  Experiment  Stations  in  Utah,  and  his  able  assistant,  L.  M. 
Winsor.  The  opinions  of  these  men  are  regarded  highly  among 
grain  growers  in  the  Mountain  States  and  in  what  follows  the 
author  has  drawn  freely  from  their  published  reports. 

GRAIN  IN  ROTATION. — The  chief  advantages  secured  by  rotat- 
ing grains,  legumes  and  root  crops  are  larger  and  better  yields,  a 
more  uniform  draft  on  the  plant  food  in  the  soil,  the  privilege  of 
growing  the  crop  best  suited  to  markets,  and  greater  immunity 
from  plant  diseases  and  crop  failures.  Grain  used  in  rotation 
serves  in  many  localities  as  a  nurse  crop  for  alfalfa  and  clover. 
However  in  planning  a  rotation  it  is  obvious  that  the  system 
adapted  to  one  locality  may  not  apply  to  another.  Each  system 
should  be  based  on  local  conditions  and  take  into  consideration 
such  factors  as  adaptability  of  soil  and  climate,  concentrated  prod- 


IRRIGATION  OF  STAPLE  CROPS  187 

nets  such  as  beef  and  cream,  market  conditions,  size  of  farm, 
availability  of  labor,  and  the  like. 

SEASONAL  ROTATION  OF  GRAIN. — Largely  as  the  result  of  ex- 
periments by  the  Irrigation  Investigations  force  in  California, 
grain  raising  in  the  Sacramento  Valley,  whether  for  hay  or  grain, 
has  of  late  taken  a  new  turn.  Here  the  practice  for  a  half 
century  has  been  to  sow  in  the  fall  or  winter  and  rely  upon  the 
winter  rains  to  provide  moisture  to  mature  the  crop  in  the 
spring.  The  success  which  has  attended  the  efforts  of  Messrs. 
Adams  and  Beckett  hi  irrigating  grain  on  the  University  Farm 
at  Davis,  California,  has  led  to  a  change  in  plan.  By  making 
use  of  irrigation  water  any  deficiency  in  the  rainfall  can  be  made 
up  and  when  the  grain  is  harvested  in  the  spring  the  stubble  can 
be  irrigated,  plowed  and  seeded  to  another  crop.  Professor 
Beckett  is  of  the  opinion  that  three  crops  can  be  grown  on  the 
same  field  each  year  provided  the  right  use  is  made  of  both  soil 
and  water.  In  any  event  grain  followed  by  a  corn  crop  has  been 
a  demonstrated  success  provided  the  soil  fertility  is  maintained 
by  a  proper  rotation. 

PREPARATION  OF  THE  SOIL. — Grain  crops  respond  quickly  at  the 
start  to  a  carefully  prepared  seed  bed.  On  heavy  soil"  it  is  not 
advisable  to  plow  very  deep  at  first,  for  the  deeper  soil,  being 
less  exposed  to  the  action  of  the  elements,  is  not  so  mellow  or  so 
well  aerated;  but  each  succeeding  plowing  should  go  a  little 
deeper  until  the  desired  depth  is  reached,  by  which  time  the  in- 
active subsoil  shall  have  become  productive.  In  breaking  up 
new  land  it  is  advisable  to  remove  if  possible  all  the  brush  and 
roots  because  when  turned  under  they  keep  the  soil  loose  and 
open  and  cause  the  ready  loss  of  moisture.  Brush  thus  covered 
will  remain  sound  for  a  long  time  before  decaying  and  will  be  a 
constant  source  of  annoyance  while  it  lasts. 

In  order  that  the  winter  moisture  may  be  stored  for  spring 
germination,  it  is  advisable  to  prepare  the  sofl  early  and  the 
ground  should  be  plowed  in  the  fall.  Fall-plowed  ground  should 
receive  a  little  cultivation  with  a  spring- tooth  harrow  as  soon  as 
it  can  be  worked  in  the  spring.  In  the  absence  of  a  spring-tooth, 
the  best  implement  is  the  spike-tooth  harrow  with  teeth  at  an 
angle  of  45  to  60  degrees.  The  disk  harrow  should  not  be  used 
in  preparing  full-plowed  ground  for  seeding  except  perhaps  in 


188  USE  OF  WATER  IN  IRRIGATION 

rare  cases,  because  it  cuts  too  deep  and  the  soil  will  dry  out  just 
as  deep  as  it  is  disturbed.  The  object  of  this  cultivation  is 
three-fold;  it  pulverizes  the  surface  mulch,  it  kills  the  first  crop 
of  weeds  which  start  with  the  early  warm  days  of  spring,  and  it 
levels  the  rough  surface  of  the  land,  leaving  it  in  better  condition 
for  irrigation.  If  this  method  is  followed,  the  moisture  will  be 
held  near  enough  the  surface  so  that  the  grain  may  be  drilled 
from  1  to  2  inches  into  the  moist  -earth  which  lies  beneath  the 
dry  surface  mulch. 

Where  it  is  necessary  to  plow  in  the  spring  care  should  be 
taken  to  have  the  ground  sufficiently  moist.  It  should  not  break 
up  into  dry  clods  or  break  down  into  a  powdery  ash  heap.  In 
the  former  case  a  suitable  seed  bed  can  not  be  secured  and  in  the 
latter  the  soil  will  puddle  after  being  wet.  When  plowed  it 
should  be  dry  enough  to  scour  the  plow  and  moist  enough  to 
turn  over  in  a  mellow  state.  When  the  soil  is  too  dry  it  is  better 
to  irrigate  before  plowing  even  though  plowing  be  delayed  in 
consequence.  The  harrow  should  follow  the  plow.  If  a  second 
team  is  not  available  then  the  land  plowed  in  the  forenoon  should 
be  harrowed  before  the  team  is  unhitched  at  dinner  time,  that 
plowed  in  the  afternoon  should  be  harrowed  before  night.  Where 
leveling  is  necessary  it  should  be  done  immediately  after  plow- 
ing and  should  be  followed  in  turn  by  light  harrowing.  This 
is  essential  in  order  to  hold  the  moisture  and  to  get  the  ground 
smoothed  down  to  a  seed  bed  while  it  is  in  a  moist  condition. 

SEED  AND  SEEDING. — The  time  of  seeding  varies  with  the 
locality  and  variety  of  grain.  Wheat  may  be  sowed  on  unfrozen 
ground  at  any  time  from  late  August  until  well  along  in  the  spring 
months.  Spring  wheat  should  be  planted  early.  It  is  generally 
conceded  that  the  growing  of  fall  or  winter  wheat  is  preferable 
to  the  growing  of  spring  wheat  except  in  sections  where  the  former 
will  winterkill.  In  growing  winter  wheat  farm  labor  is  more 
evenly  distributed,  less  water  and  labor  are  required  in  irrigation 
and  the  crop  matures  earlier.  These  advantages  also  apply  to 
the  grains  which  can  be  grown  in  the  fall. 

In  the  case  of  spring  barley  and  oats,  early  planting  is  not 
desirable.  When  sown  too  early  these  seeds  sometimes  rot  be- 
fore germinating  and  a  good  stand  is  not  secured.  The  better 
plan  is  to  have  the  ground  well  prepared  with  plenty  of  moisture 


IRRIGATION  OF  STAPLE  CROPS  189 

under  a  thin,  fine  mulch;  then  wait  for  warm  spring  weather  and 
plant  at  a  time  when  quick  germination  can  be  secured. 

The  depth  of  planting  will  depend  somewhat  on  the  condition 
of  the  soil.  One  of  the  advantages  in  using  a  drill  in  seeding  is 
to  secure  a  uniform  germination  which  in  turn  insures  a  uniform 
ripening  of  the  crop.  When  a  drill  is  used  in  seeding  the  grain 
should  be  placed  1/2  to  2  inches  in  the  moist  earth  which  with 
a  2  to  2  1/2  inch  mulch  makes  a  total  depth  of  planting  of  from 
2  1/2  to  4  1/2  inches. 

The  variety  of  seed  to  use  should  be  determined  by  local  con- 
ditions, time  of  planting,  market  demands  and  various  other 
factors.  A  safe  rule  to  follow  is  to  choose  the  variety  which  has 
been  adopted  by  the  majority  in  a  community  and  found  to  give 
the  best  results.  If  any  entire  community  is  growing  the  same 
variety  there  will  be  little  difficulty  experienced  in  obtaining 
seed  pure,  which  is  one  of  the  most  important  considerations  in 
successful  grain  culture.  Care  should  also  be  taken  to  secure 
grain  seed  which  is  true  to  type,  heavy,  and  free  from  weed  seed. 
This  done,  the  next  step  is  the  proper  treatment  of  the  seed  to 
prevent  various  diseases,  principal  among  which  is  smut. 

The  Department  of  Agriculture  and  the  state  experiment 
stations  have  recommended  various  treatments  to  kill  the  smut 
spore  without  impairing  the  germinating  power  of  the  grain,  such 
as  a  solution  of  blue  stone  followed  by  lime,  immersion  in  hot 
water,  sprinkling  with  or  immersion  in  formalin  solution,  details 
of  which  are  given  in  Farmers'  Bull.  250  of  the  Department  of 
Agriculture.  The  formalin  treatment  consisting  of  1  pound  of 
formalin  of  guaranteed  strength  and  purity  to  50  gallons  of  water 
is  commonly  used  at  the  present  time. 

IRRIGATION  BEFORE  SEEDING. — In  many  parts  of  the  arid  West 
the  winter  precipitation  is  so  light  that  moisture  sufficient  for 
spring  germination  is  not  stored  in  the  soil  and  it  is  necessary 
to  irrigate  to  supply  the  deficiency.  This  may  be  done  either 
before  or  after  seeding.  Although  the  latter  practice  is  the 
more  common,  observations  and  the  results  of  demonstrations 
in  many  western  states  point  conclusively  to  the  fact  that  irri- 
gation before  seeding  rather  than  immediately  afterward  is 
generally  the  better  practice.  In  the  more  retentive  soils  of  the 
warmer  states,  water  may  be  applied  during  the  late  fall  or 


190  USE  OF  WATER  IN  IRRIGATION 

winter  months  so  as  to  store  enough  moisture  in  the  soil  to  supply 
the  needs  of  the  plant  until  seeding  time.  In  other  localities 
the  effect  of  fall  plowing  followed  by  soil  moisture  conservation 
may  provide  sufficient  moisture  without  any  artificial  watering. 

It  is  the  land  which  is  plowed  in  the  spring  that  gives  the 
most  trouble.  If  it  is  too  dry  it  should  first  be  plowed  and  leveled, 
and  then  irrigated  and  harrowed  when  dry  enough.  The  har- 
rowing should  be  done  with  a  spring-tooth  or  spike-tooth  har- 
row. This  treatment  not  only  provides  ample  moisture  near 
the  surface  but  leaves  the  soil  mellow  and  in  good  condition  to 
insure  an  even  and  rapid  growth  of  grain.  It  is  only  on  the  more 
retentive  soils  that  this  practice  is  likely  to  prove  injurious  in 
seeding. 

Farmers  who  plow  in  the  spring,  put  in  the  seed  and  take 
chances  of  the  small  amount  of  moisture  in  the  soil  being  suf- 
ficient for  germination,  usually  fail  to  harvest  a  full  crop.  The 
stirring  of  the  soil  causes  a  loss  of  moisture  by  evaporation  in  the 
top  layer  where  the  seed  is  placed,  and  as  a  result  germination 
is  incomplete  and  an  immediate  irrigation  is  necessary  to  obtain 
a  stand.  The  application  of  water  at  this  time  is  liable  to  form 
a  crust  through  which  the  young  plants  can  not  force  their  way. 
This  crust  also  tends  to  rob  the  soil  of  its  moisture  by  producing 
a  heavy  evaporation  and  it  is  not  long  until  a  second  or  even  a 
third  watering  is  required.  These  frequent  irrigations  at  the 
start  produce  shallow-rooted  plants  which  are  injuriously  affected 
by  the  subsequent  drying  out  of  the  top  soil.  The  bad  effects 
of  "irrigating  up"  a  crop,  as  it  is  called,  may  be  partially  remedied 
by  harrowing  the  ground  in  the  direction  of  the  furrows  when  the 
plants  are  in  the  third  or  fourth  leaf. 

WHEN  TO  IRRIGATE. — There  are  two  critical  periods  in  the 
development  of  grain  crops.  The  first  extends  from  germination 
until  the  plants  shade  the  ground,  the  second  is  at  the  flowering 
or  fruiting  stage.  The  plant  must  get  a  good  start.  Sufficient 
food  is  present  in  the  parent  kernel  to  start  the  root  growth  and 
to  force  the  first  leaf  into  view,  after  which  it  must  shift  for  itself. 
If  moisture  is  scarce  at  this  stage  the  necessary  food  can  not  be  ob- 
tained and  a  stunted  growth  results  which  can  never  be  entirely 
overcome.  Because  of  the  necessity  of  giving  the  tender  plant 
a  good  start  it  is  important  that  the  moisture  should  be  supplied 


IRRIGATION  OF  STAPLE  CROPS  191 

beforehand  so  as  to  make  it  unnecessary  to  apply  cold  water, 
which  always  checks  development  at  this  stage  of  growth. 

The  second  critical  period  and  the  one  which  is  the  most  vital 
because  of  the  sensitive  condition  of  the  plant,  comes  at  the 
flowering  or  fruiting  stage.  More  moisture  is  required  at  this 
time  and  immediately  following  than  at  any  other  stage  of 
growth.  To  avoid  a  second  shock  care  should  be  taken  to  supply 
plenty  of  moisture  about  booting  time  before  the  heads  appear. 
This-  irrigation  may  suffice  to  bring  the  crop  to  maturity.  How- 
ever, if  a  shallow-rooted  system  has  been  developed  by  frequent 
previous  irrigations  or  if  even  with  a  deep-rooted  system  there 
seems  to  be  a  scant  supply  of  moisture,  then  it  is  advisable  to 
give  another  light  irrigation  when  the  grain  is  in  the  dough. 
Otherwise  it  will  not  fill  and  will  shrink  in  weight  after  harvest. 

The  character  of  the  soil  and  subsoil  (Farmers'  Bui.  399) 
has  a  large  influence  on  the  time  of  irrigating.  A  heavy  soil  with 
tight  subsoil  will  receive  a  large  quantity  of  moisture  and  hold 
it  for  a  long  time,  making  it  possible  to  irrigate  heavily  and  at 
long  intervals.  A  lighter  soil  which  is  underlaid  with  an  open 
subsoil  will  not  retain  the  water  and  it  will  become  necessary  to 
irrigate  more  frequently. 

Many  natural  and  artificial  conditions  influence  the  time  and 
the  amount  of  irrigation,  and  the  farmer  who  best  understands 
and  makes  use  of  them  is  the  most  successful.  The  condition 
of  the  soil,  together  with  the  appearance  of  the  plant  affords  a 
practical  test  of  the  requirement  of  the  plant  for  water.  Grain 
which  has  plenty  of  moisture  is  of  a  light  green  color;  but  when 
the  plant  begins  to  suffer  for  water  it  turns  to  a  dark  green  and  the 
lower  leaves  begin  to  turn  yellow.  The  presence  of  alkali  in  the 
soil  may  produce  the  same  effect,  however. 

QIAXTITY  OF  WATER  TO  APPLY. — The  quantity  of  water  to 
be  applied  at  each  irrigation  depends  upon  the  number  of  irri- 
gations, depth  of  soil,  nature  of  subsoil,  the  purpose  for  which 
the  grain  is  grown,  the  condition  of  the  crop,  climatic  condi- 
tions, and  from  a  practical  standpoint,  the  length  of  time  be- 
tween water  turns,  the  available  supply,  method  of  application, 
the  requirements  of  other  crops,  the  expertness  of  the  irrigator 
and  the  length  of  time  the  field  has  been  under  irrigation  and 
cultivation  (Farmers'  Bui.  399). 


192  USE  OF  WATER  IN  IRRIGATION 

As  a  general  rule  the  soil  is  driest  at  the  time  of  the  first  irri- 
gation and  more  water  will  be  required  to  irrigate  properly  at 
this  time  than  subsequently.  It  is  always  safe  to  assume  that 
the  larger  the  growth  of  the  straw  the  greater  will  be  the  quantity 
of  water  required  at  the  time  the  head  is  making.  Water  for 
irrigation  is  generally  plentiful  during  the  early  spring,  but  at 
the  time  the  grain  is  filling  the  supply  usually  begins  to  fail. 
The  usual  practice  of  the  farmers  in  the  Mountain  States  is  to 
'irrigate  heavily  in  the  spring  and  use  less  water  as  the  season 
advances. 

The  amount  of  water  required  by  new  land  is  usually  more  than 
that  required  by  older  land.  The  experience  of  the  Bear  Valley 
Canal  Company  in  Utah  affords  an  excellent  illustration  of  the 
relative  requirements  in  this  regard.  During  the  first  years 
of  irrigation  in  this  valley  a  second-foot  of  water  was  used  upon 
60  to  80  acres  and  apparently  the  land  required  that  amount. 
In  recent  years  the  amount  of  land  actually  served  by  a  second- 
foot  of  water  averaged  163  acres  for  grain  crops.  This  decrease 
in  the  use  of  water  is  due  in  the  first  place  to  a  rise  of  the  ground 
water  level  and  in  the  second  to  a  better  understanding  of  the 
water  requirements  of  crops  and  improved  methods  of  culture. 

The  time  of  irrigation  in  connection  with  the  stage  of  growth 
has  much  to  do  in  determining  the  amount  of  straw  as  compared 
with  the  amount  of  grain  produced  by  the  plant.  The  grain  plant 
passes  through  a  period  when  it  is  making  straw  and  roots,  and 
a  period  when  it  is  making  head.  A  heavy  supply  of  moisture 
during  the  first  period  is  conducive  to  a  heavy  growth  of  straw 
and  leaves.  If  this  is  followed  by  a  shortage  of  moisture  during 
the  second  or  heading  stage,  the  heads  will  not  fill  and  a  shrunken 
kernel  results.  A  proper  supply  of  moisture  at  both  stages  in- 
sures a  normal  growth  of  straw  with  plump,  well-filled  heads  of 
grain.  These  observations  seem  to  indicate  that  the  time  of 
irrigation  has  more  effect  upon  the  results  than  does  the  quantity 
of  water  applied. 

In  general,  beginning  with  grain  under  dry  farm  conditions, 
the  yields  can  be  slightly  increased  with  each  added  amount  of 
water  until  the  maximum  yield  is  reached.  Beyond  this  point 
a  condition  is  finally  reached  when  an  increased  amount  of 
water  actually  causes  a  falling  off  in  yield.  It  may  be  well 


IRRIGATION  OF  STAPLE  CROPS  193 

to  state  in  this  connection  that  the  increase  in  yield  is  not  in 
proportion  to  the  increase  in  water  applied  so  that  where  water 
is  scarce  a  heavy  application  may  be  given  at  a  loss  to  the  farmer 
even  though  the  limit  of  application  for  maximum  yield  has  not 
been  reached. 

The  results  of  investigations  made  by  Don  H.  Bark  on  the 
medium  clay  and  sandy  loam  soils  in  southern  Idaho  in  the 
years  1910,  1911  and  1912  show  that  the  average  amount  of 
water  used  on  122  fields  of  grain  was  1.45  acre-feet  per  acre.  The 
rainfall  during  the  three  seasons  of  growth  varied  from  2  to 
6  inches. 

In  the  years  1899  and  1902  inclusive,  the  writer  determined 
the  amount  of  water  used  on  25  grain  fields  in  three  widely 
separated  valleys  of  Montana  and  the  average  was  found  to  be 
1.31  acre-feet  per  acre.  To  this  amount  should  be  added  the 
rainfall  which  averaged  0.42  acre-foot  per  season. 

METHODS  OF  APPLYING  WATER. — The  experience  of  the  Greeley 
colonists  in  Colorado  and  of  others  throughout  the  West  goes 
far  in  demonstrating  that  grain  growing  year  after  year  on 
irrigated  land  is  not  a  profitable  business.  In  order  to  yield 
fairly  remunerative  returns  it  must  be  rotated  with  other  crops. 
Accordingly  the  preparation  of  land  and  the  manner  of  applying 
water  must  also  be  adapted,  not  only  to  grain  but  to  other 
crops  in  the  rotation.  At  least  three  of  the  various  methods 
previously  described  are  suited  to  a  combination  of  this  kind. 
These  methods  are  flooding,  small  furrows  and  borders. 

Irrigating  grain  by  flooding  is  the  usual  practice  in  Montana. 
There  the  field  ditches,  spaced  from  60  to  90  feet  apart,  are  made 
with  a  14-  or  16-inch  double  mouldboard  plow  attached  to  a  sulky 
frame  and  drawn  by  three  horses.  The  ditches  are  cleaned 
out  with  a  steel  or  wooden  shovel  of  the  same  width,  drawn  by  one 
horse,  Fig.  64.  This  implement  also  forms  the  earth  dams  in  the 
ditches  and  is  locally  styled  a  dammer.  The  horse  walks  in  the 
furrow  made  by  the  ditch  plow  and  the  loose  earth  in  the  bottom 
and  sides  is  carried  by  the  steel  shovel  and  dumped  in  heaps  about 
60  feet  apart.  A  stream  of  100  miner's  inches  or  thereabouts  is 
turned  into  the  supply  ditch  and  divided  between  two  adjacent 
field  ditches.  When  one  piece  of  ground  is  thoroughly  soaked  to 
a  depth  of  12  inches  the  dam  is  opened  and  the  water  rushes 

13 


194  USE  OF  WATER  IN  IRRIGATION 

through  until  it  is  checked  by  the  next  earth  dam.  By  this 
method  and  with  a  good  head  of  water  one  man  can  irrigate  on  an 
average  5  acres  per  day.  If  the  flow  of  water  is  small  and 
intermittent  the  average  may  be  cut  down  to  2  acres.  The 
second  irrigation  is  applied  in  the  same  way  but  the  amount  of 
water  used  is  considerably  less. 

In  some  sections  of  the  West  the  field  ditches,  instead  of  being 
located  on  the  grade  lines  .extend  down  the  steepest  slope. 
Each  irrigator  is  given  about  125  miner's  inches  of  water  which 
is  divided  between  two  laterals.  Instead  of  earth,  half-rotted 
straw  or  stable  manure  is  often  used  to  form  the  checks,  which 


FIG.  64. — Dammer  used  in  cleaning  and  damming  field  laterals. 

are  spaced  about  65  feet  apart.  As  soon  as  the  first  irrigation 
is  completed  the  dams  are  re-set  for  the  second  irrigation.  In 
.re-setting  the  dams  the  manure  or  straw  is  mixed  with  the 
earth  while  both  are  kept  damp  thus  forming  a  stronger  and 
more  impervious  dam. 

In  irrigating  grains  by  small  furrows  spaced  2  1/2  to  3  feet 
apart,  commonly  called  corrugations  (Art.  17),  from  1  to 
2  second-feet  is  turned  into  the  head  ditches  and  distributed 
among  the  furrows.  One  second-foot  may  well  be  divided  among 
50  to  150  furrows  depending  on  the  character  of  the  soil  and  the 
slope  of  the  field.  The  length  of  the  furrows  should  not  ex- 
ceed that  of  a  square  10-acre  tract  (660  feet)  and  when  a  40- 
acre  field  is  irrigated  it  should  be  divided  into  three  equal  parts 


IRRIGATION  OF  STAPLE  CROPS  195 

by  head  ditches,  thus  making  the  length  of  furrow  in  each 
part  440  feet.  The  water  should  be  run  long  enough  in  the  fur- 
rows to  moisten  the  soil  between  them. 

The  irrigation  of  grain  by  the  border  method  (Art.  20)  does 
not  differ  in  any  essential  from  the  description  given  elsewhere 
for  the  irrigation  of  alfalfa  and  other  crops  by  this  method. 

HARVESTING,  MARKETING  AND  PROFITS. — Irrigated  grain  is  con- 
fined to  relatively  small  areas  and  has  a  long  and  heavy  straw. 
Both  of  these  conditions  are  unsuited  to  the  combined  harvester 
so  commonly  used  on  the  dry  farms  and  in  the  Mississippi 
valley.  The  sheaf  binder  is  used  almost  universally  in  harvest- 
ing irrigated  grain.  This  implement  drops  the  grain  bound  in 
bundles  either  scattered  or  in  piles.  These  are  immediately 
placed  in  shocks  by  hand.  Occasionally  the  bundles  are  hauled 
from  the  shocks  to  the  farm  stack  yard  to  cure  but  more  often 
they  are  hauled  from  the  shocks  directly  to  the  thresher. 

The  well-managed  irrigated  farm  has  very  little  grain  to 
market.  But  little  wheat  is  grown  and  the  oats,  barley  and 
corn  or  other  grains  are  fed  to  stock  of  various  kinds,  thus 
insuring  a  much  higher  return  than  can  be  realized  from  the 
direct  sale  of  the  grain. 

The  returns  which  may  be  expected  from  grain  where  it  is 
marketed  direct  are  outlined  by  Professor  McLaughlin  in 
Farmers'  Bui.  399. 

37.  Growing  Root  Crops  under  Irrigation. — Under  this  head- 
ing is  included  potatoes,  sugar  beets,  sweet  potatoes,  turnips, 
etc.,  but  in  irrigated  sections  only  the  first  two  named  are  of 
sufficient  importance  to  be  considered  here.  Root  crops  are  of 
greater  relative  importance  in  arid  than  in  humid  regions  owing 
to  the  fact  that  under  irrigation  they  produce  heavy  yields  which 
are  ordinarily  sold  for  cash.  Since  the  various  operations  con- 
nected with  the  cultivation,  irrigation,  harvesting,  etc.,  of  these 
two  crops  differ  considerably  they  will  be  treated  separately. 

POTATOES 

CLIMATE. — Potatoes  thrive  in  almost  every  section  of  the  arid 
West.  They  are  grown  successfully  in  Wyoming  at  an  elevation 
of  8000  feet  and  also  at  the  lower  elevations  in  the  states  along 


196  USE  OF  WATER  IN  IRRIGATION 

the  Pacific  coast  and  are  found  from  Montana  on  the  north 
to  New  Mexico  and  Arizona  on  the  south.  Intense  heat  is 
detrimental  to  the  potato.  In  general  it  may  be  said  that  for  the 
best  yield  the  mean  temperature  of  the  air  should  not  rise  above 
70  to  75  degrees  F.  for  any  considerable  time  while  the  tubers 
are  growing. 

SOIL. — Potatoes  under  irrigation  require  a  loose  friable  soil 
with  good  under  drainage,  an  ideal  soil  being  a  sandy  loam  with 
gravelly  subsoil.  A  heavy  clay  or  adobe  soil  is  not  well  adapted 
to  this  crop. 

ROTATION. — Some  system  of  rotation  is  very  essential  for  the 
best  results  in  the  growing  of  potatoes,  for  continuous  cropping 
will  exhaust  the  soil  in  a  short  time  and  the  yields  will  decline 
unless  fertilizers  are  applied.  Even  though  manure  or  arti- 
ficial fertilizer  is  applied,  fungus  diseases,  such  as  scab,  will 
attack  the  tubers  if  they  are  grown  on  the  same  ground  year 
after  year.  In  the  West,  alfalfa  or  clover  should  be  included 
in  any  rotation  with  potatoes  in  order  to  restore  the  nitrogen 
taken  from  the  soil  by  the  potatoes.  Small  grain  and  sugar  beets 
can  also  be  grown  to  advantage  in  such  a  rotation  though  many 
farmers  simply  grow  alfalfa  and  potatoes  alternately,  letting 
the  alfalfa  remain  3  to  5  years  or  longer  and  following 
with  potatoes  for  1  or  2  years,  never  more  than  two.  If 
grain  is  grown  the  order  should  be  alfalfa,  potatoes,  grain;  or 
alfalfa,  grain,  potatoes,  grain.  The  advantage  of  the  last 
named  rotation  is  that  the  alfalfa  is  sometimes  hard  to  kill 
out  and  if  a  crop  of  grain  is  grown  preceding  the  potato  crop 
the  alfalfa  will  be  effectually  eliminated. 

PREPARATION  OF  SOIL. — The  ground  should  be  carefully  leveled 
to  a  uniform  slope  so  that  the  irrigation  water  can  be  easily  con- 
fined to  the  furrows.  The  importance  of  deep  plowing, followed 
by  a  thorough  harrowing  in  order  to  put  the  soil  in  good  shape  to 
receive  the  seed  can  not  be  too  strongly  recommended.  If  the 
season  has  been  unusually  dry  it  is  sometimes  advisable  to  irri- 
gate before  plowing  in  order  to  insure  a  liberal  supply  of  moisture 
at  the  time  of  planting. 

SEED  AND  PLANTING. — Medium-sized  potatoes,  with  clear, 
healthy  skins-  and  shallow  eyes  should  be  selected  for  planting. 
The  grower  will  find  it  of  advantage  to  select  his  seed  potatoes 


IRRIGATION  OF  STAPLE  CROPS  197 

in  the  field,  choosing  seed  from  the  large  hills.  Ground  which 
has  grown  scabby  potatoes  the  previous  year  should  not  again 
be  planted  to  potatoes  no  matter  how  thoroughly  the  seed  may 
be  treated  to  prevent  this  disease.  If  there  is  danger  of  scab, 
ground  should  be  selected  where  alfalfa  or  grain  has  been  grown 
for  a  number  of  years.  As  an  extra  precaution  it  is  well  to  treat 
the  seed  before  cutting  with  a  solution  of  corrosive  sublimate  or 
formalin  or  with  gas.  Farmers'  Bui.  407  of  the  Department  of 
Agriculture  describes  the  preparation  and  use  of  these  solutions. 
The  pieces  should  not  be  cut  too  small,  quarters  or  halves  usually 
being  recommended  by  the  best  growers.  Many  good  authorities 
are  now  recommending  the  planting  of  whole  potatoes  of  medium 
size. 

The  tubers  should  be  planted  3  to  6  inches  deep  and  12  to  18 
inches  apart  in  rows  2  1/2  to  3  1/2  feet  apart,  depending  on  local 
conditions.  Shallow  planting  is  best  on  heavy  soils,  while  on 
light  sandy  soils  6  inches  or  even  more  is  not  considered  too  deep. 
The  amount  of  seed  per  acre  depends,  of  course,  on  the  distance 
between  hills  and  the  size  of  the  seed  pieces,  but  700  pounds  may 
be  considered  a  fair  average.  Where  this  crop  is  grown  on  a 
commercial  scale  a  planter  should  be  used  but  great  care  should 
be  exercised  to  get  a  uniform  stand.  Planting  potatoes  in  plow 
furrows  should  never  be  practised  as  the  seed  should  be  entirely 
surrounded  with  soft  earth  to  permit  of  the  proper  development 
of  the  roots  and  tubers. 

CULTIVATION. — In  arid  regions  frequent  cultivation  will  aid 
greatly  in  conserving  the  soil  moisture  and  may  take  the  place  of 
one  or  more  irrigations.  While  the  plants  are  quite  small  the 
field  can  be  harrowed  without  injury  and  this  kills  the  small 
weeds  and  serves  as  a  cultivation.  Other  cultivations  between 
the  rows  with  an  ordinary  cultivator  should  follow  rapidly  until 
the  vines  are  large  enough  to  shade  the  ground  when  it  is  usually 
considered  that  no  further  cultivation  is  necessary  although 
some  irrigators  prefer  to  cultivate  after  every  irrigation  so  long 
as  it  can  be  done  without  injury  to  the  vines.  These  later  culti- 
vations should  be  very  shallow,  however,  in  order  not  to  injure 
the  tubers. 

SPRAYING. — It  is  sometimes  necessary  to  spray  potato  vines 
to  protect  them  against  the  ravages  of  the  potato  beetle.  There 


198  USE  OF  WATER  IN  IRRIGATION 

are  machines  on  the  market  which  enable  the  grower  to  get  over 
his  fields  very  rapidly  and  a  thorough  spraying  at  the  right 
time  greatly  reduces  the  injury  by  the  beetles.  In  Farmers' 
Bui.  407  the  Bordeaux  mixture  is  recommended.  The  method 
of  making  small  quantities  of  this  mixture  is  as  follows:  " Place 
5  pounds  of  lime  in  one  tub  and  slake  this  with  sufficient  water 
to  thoroughly  break  up  the  lime  without  allowing  it  to  burn. 
After  the  lime  is  slaked,  dilute  it  to  25  gallons.  Into  another 
tub  pour  25  gallons  of  water  and  suspend  in  it  a  5-pound  sack  of 
copper  sulphate  for  24  to  48  hours.  Bordeaux  mixture  is  made 
by  pouring  these  two  solutions  through  a  wire  cloth  sieve  having 
about  18  to  20  meshes  per  inch,  equal  quantities  of  the  two 
solutions  being  poured  at  the  same  time  through  the  strainer." 

IRRIGATION. — Potatoes  should  never  be  "  irrigated  up,"  that  is, 
it  should  never  be  necessary  to  irrigate  the  field  to  sprout  the 
seed,  as  it  is  impossible  to  get  a  uniform  stand  in  that  way. 
Care  should  be  taken  that  sufficient  moisture  is  in  the  ground 
at  the  time  of  planting  to  supply  the  needs  of  the  plant  for  the 
first  20  days.  Irrigation  should  be  delayed  as  long  as  possible 
without  checking  the  healthy,  vigorous  growth  of  the  vines. 
Under  ordinary  circumstances  the  first  irrigation  is  applied  about 
the  time  the  vines  begin  to  bloom  and  from  this  time  on  until 
maturity  the  soil  should  be  kept  well  supplied  with  moisture  so 
as  not  to  check  the  growth.  Allowing  the  soil  to  dry  out  and 
then  applying  a  copious  irrigation  is  apt  to  produce  knotty  tubers 
and  otherwise  injure  their  quality. 

Furrow  irrigation  is  the  only  practical  method  for  potatoes. 
The  common  practice  in  irrigating  potatoes  is  to  make  an  open- 
ing in  the  ditch  bank  with  the  shovel  at  intervals,  one  opening 
supplying  water  to  several  furrows.  This  method  can  be  im- 
proved on  by  inserting  wooden  or  metal  spouts  in  the  ditch  bank 
for  every  other  row  and  raising  the  water  in  the  ditch  by  means 
of  a  check  box  or  canvas  dam  until  it  flows  through  these  open- 
ings. This  enables  the  irrigator  to  control  the  flow  of  water  in 
each  furrow  much  better  than  by  the  first-mentioned  plan. 
A  rather  unique  method  of  supplying  water  to  the  furrows  is 
employed  in  parts  of  Colorado  and  is  shown  in  Fig.  65.  When 
furrow  E  has  been  watered  the  ridge  between  it  and  furrow  F  is 
cut,  the  earth  removed  being  placed  in  furrow  E  to  turn  the 


IRRIGATION  OF  STAPLE  CROPS 


199 


water  through  the  cut.  This  is  repeated  for  the  next  furrow 
and  so  on  until  the  group  of  furrows  supplied  from  an  opening  in 
the  ditch  has  been  watered. 

Furrows  should  be  made  deep  so  as  to  allow  the  water  to 
be  drawn  up  to  the  vines  by  capillarity.  This  lessens  the 
danger  of  saturating  the  soil  and  causing  it  to  bake,  a  condition 
which  should  always  be  avoided  if  possible.  At  the  last  culti- 
vation  before  the  first  irrigation  the  fenders  should  be  taken 
off  the  cultivator  and  the  shovels  turned  so  as  to  crowd  the 

>^g5^SS^^  ' ' " 

BWI^ 

'/2  *2"  « 36 '^Su/- faced  / S/tfe, Htoo^c/.    ---  -.>  V-^  • 


A          B         C        D 
FIG.  65. — Method  of  distributing  water  from  head  ditch  to  potato  rows. 

earth  toward  the  vines.  The  furrow  thus  made  should  be  deep- 
ened by  going  over  the  field  again,  using  double-winged  shovels 
on  the  cultivator  or  a  double  mouldboard  plow.  This  makes  a 
furrow  about  12  inches  deep  measured  from  the  crown  of  the 
plants  and  12  to  16  inches  wide  across  the  top.  The  chief  ad- 
vantages of  deep  furrows  are :  they  provide  an  abundance  of  loose 
earth  to  place  around  the  tubers;  they  lessen  the  risk  of  the  water 
coming  in  contact  with  the  vines;  they  prevent  an  excess  of  water 
around  the  tubers  and  they  allow  the  moisture  to  be  drawn  up 
from  below,  thus  supplying  a  constant  and  uniform  quantity  to 
the  roots. 

Where  it  is  possible  to  get  a  large  head  of  water,  one  irrigator 
can  handle  2  second-feet  without  waste.     With  such  a  stream 


200  USE  OF  WATER  IN  IRRIGATION 

he  can  keep  water  running  in  40  to  50  rows  at  a  time  and  under 
typical  conditions,  that  is,  with  a  slope  of  25  feet  per  mile  and 
rows  1000  to  1200  feet  long,  the  water  should  reach  the  end 
of  the  rows  in  3  or  4  hours.  Where  smaller  heads  must 
be  used  it  is  sometimes  necessary  to  run  water  in  the  rows 
from  24  to  48  hours  in  order  to  thoroughly  irrigate  the  crop. 
Two  or  three  irrigations  usually  suffice  to  bring  the  crop  to 
maturity.  A  well-known  method  of  determining  when  the  crop 
is  in  need  of  moisture  is  to  dig  into  the  earth  near  the  tubers 
and  press  a  handful  together;  if  it  crumbles  apart  when  released 
the  crop  should  be  irrigated.  When  the  vines  have  a  dark 
green  color  it  is  also  an  indication  that  they  need  water. 

Experiments  conducted  at  the  Experiment  Stations  of  Idaho, 
Montana  and  Utah  indicate  that  better  quality  and  as  good 
yields  of  potatoes  can  be  secured  by  the  use  of  a  moderate 
amount  of  water.  The  amount  required  varies  with  the  soil, 
and  the  season,  but  generally  speaking  the  total  amount  applied 
during  a  season  should  not  exceed  2  feet  in  depth  over  the 
field.  With  frequent  cultivations  and  care  in  the  distribution 
of  the  water  a  much  smaller  amount  will  be  ample. 

Opinions  differ  regarding  the  respective  merits  of  applying 
water  in  every  row  or  every  alternate  row.  The  majority 
of  potato  growers  irrigate  in  every  row  but  many  employ  the 
alternate  method  successfully.  With  a  loose,  friable,  sandy 
loam  which  allows  moisture  to  spread  rapidly  laterally  water 
applied  to  every  other  furrow  will  moisten  the  intervening 
space  sufficiently  to  maintain  the  proper  condition  of  soil  mois- 
ture. At  the  second  irrigation  the  rows  not  watered  the  first 
time  should  be  irrigated.  Where  only  a  small  irrigation  head 
is  obtainable,  and  with  a  soil  as  described  above,  this  method 
undoubtedly  possesses  merit. 

Under  any  system  of  irrigation,  care  should  be  used  to  cease 
irrigating  long  enough  before  harvest  to  allow  the  ground  to 
become  dry  so  that  the  dirt  will  readily  separate  from  the  tubers 
when  they  are  plowed  out. 

The  writer  is  indebted  to  Mr.  Guy  Ervin,  of  the  U.  S. 
Department  of  Agriculture,  for  the  following  suggestions  as  to 
the  best  practice  to  follow  in  irrigating  potatoes. 

1.  See  that  there  is  plenty  of  moisture  in  the  soil  at  the  time  of 


IRRIGATION  OF  STAPLE  CROPS  201 

planting.     Irrigate  before  planting  if  necessary  but  never  irri- 
gate to  sprout  the  seed  after  planting. 

2.  Run  a  small  stream  of  water  in  a  deep  furrow  so  that  mois- 
ture will  be  drawn  up  to  the  tubers  instead  of  soaking  down  to 
them. 

3.  Do  not  irrigate  too  soon.     Wait  until  the  crop  is  plainly 
in  need  of  water  and  then  keep  the  ground  well  supplied  with 
moisture  until  the  potatoes  have  matured. 

4.  Conserve  the  moisture  and  aerate  the  soil  by  frequent  light 
cultivations.     If  this  is  done  two  or  three  irrigations  will  usually 
suffice. 

HARVESTING  AND  SORTING. — When  the  skin  of  the  potato  is  firm 
and  cannot  be  rubbed  off  and  the  vines  are  dead,  the  crop  is  ready 
to  harvest.  The  work  of  digging,  sorting  and  marketing  or  stor- 
ing should  then  be  rushed  through  in  order  to  avoid  danger  of  loss 
from  freezing. 

Where  potatoes  are  grown  on  a  commercial  scale  it  is  best  to 
have  a  potato  digger.  Sometimes  a  number  of  farmers  can  com- 
bine and  purchase  a  digger  to  advantage.  There  are  a  number  of 
different  makes  on  the  market  at  varying  prices.  The  machine 
should  be  kept  some  distance  ahead  of  the  pickers  in  order  that 
the  potatoes  may  have  time  to  dry  off  before  they  are  sacked. 

The  sorting  can  either  be  done  in  the  field  at  the  time  of  harvest 
or  later  when  they  are  to  be  marketed  but  the  former  method  is 
the  better.  There  are  also  machines  which  sort  the  potatoes. 
These  consist  simply  of  a  set  of  screens  of  different  sized  meshes 
which  separate  the  small  potatoes  from  those  of  marketable  size. 

STORING. — It  is  not  always  convenient  or  advisable  to  haul  the 
potatoes  directly  to  market  from  the  field  and  it  is  therefore 
often  necessary  to  provide  storage  for  part  of  the  crop  at  least. 
In  building  a  storage  house  for  potatoes  it  should  be  constructed 
so  as  to  provide  an  even  temperature  just  a  little  above  freezing, 
a  good  circulation  of  dry  air  and  convenient  arrangem3nts  for 
putting  in  and  taking  out  potatoes. 

Fig.  66  shows  an  end  elevation  of  a  potato  cellar  near  Idaho 
Falls,  Idaho.  The  cellar  is  98  feet  long  and  40  feet  wide.  The 
dimensions  of  the  frame  are  as  shown  in  the  sketch.  The  sides 
and  ends  are  boarded  up  with  1-inch  rough  lumber  and  the  por- 
tions above  the  natural  surface  of  the  ground  are  banked  with 


202 


USE  OF  WATER  IN  IRRIGATION 


earth  and  straw.  The  roof  consists  of  2-inch  rough  planking 
covered  with  a  foot  each  of  straw  and  packed  earth.  The  main 
entrance  is  protected  by  a  covered  driveway  28  feet  long,  11  feet 
wide  and  9  feet  high  built  of  rough  1-inch  lumber.  There  are 
six  1-foot  square  chutes  in  the  roof  on  each  side  for  use  in  filling 
the  top  part  of  the  cellar  and  four  2  X  3-foot  traps  in  center  of 
roof  to  admit  light  and  air.  In  cold  weather  the  traps  are  covered 
with  sacks  and  in  very  severe  weather  a  covering  of  fresh  barn- 
yard manure  is  added. 


2  PCS  3  x  12  to  Hold  Door 


2  Driven  Tongue 


FIG.  66. — End  elevation  of  a  potato  cellar. 

MARKETING. — The  man  who  grows  potatoes  commercially 
should  keep  in  close  touch  not  only  with  his  local  market  but  also 
with  the  large  markets  of  the  country.  He  should  endeavor  to 
ascertain  just  what  characteristics  a  potato  should  possess  to  be 
a  good  seller  and  should  strive  to  produce  that  kind  of  potato. 
Very  large  or  very  small  potatoes  are  not  in  demand.  A  medium- 
sized  potato,  with  shallow  eyes  and  smooth,  healthy  skin  will 
always  command  the  highest  price.  If  the  grower  contemplates 
holding  his  crop  in  storage  for  better  prices  he  should  take  into 
account  the  extra  labor  involved,  the  loss  from  shrinkage  of  the 
stored  crop  and  the  danger  of  loss  from  freezing  in  very  cold 
weather  or  from  other  causes.  Cooperation  among  growers  in 
raising  uniform  varieties  and  in  marketing  their  crops  is  of  great 
value  in  sections  which  are  distant  from  large  markets. 

COST  OF  GROWING. — The  cost  of  growing  potatoes  under  irriga- 
tion varies  somewhat  due  to  the  difference  in  the  amount  of  seed 
planted,  the  price  of  the  irrigation  water,  the  yield,  etc.  How- 
ever, it  is  believed  the  following  tabulation  represents  the  average 
cost  of  the  various  items.  This  does  not  include  the  cost  of 


IRRIGATION  OF  STAPLE  CROPS  203 

fertilizer  which  if  used  would  add  S3  or  $4,  or  taxes  and  interest 
on  the  value  of  the  land. 

Preparing  ground $2 . 50 

Cutting  seed  and  planting 2 . 00 

Cost  of  seed 8 . 00 

Cultivating  and  hoeing 4 . 00 

Irrigating 4 . 50 

Harvesting 8 . 00 

Sorting 1 . 50 

Sacks 5.00 

Marketing 5.00 

Spraying 2.00 


Total $42.50 

The  cost  of  the  seed  is  the  item  subject  to  the  greatest  variation. 
This  is  readily  understood  when  it  is  remembered  that  the  amount 
of  seed  planted  may  vary  all  the  way  from  600  to  3000  pounds 
per  acre. 

YIELDS  AND  PROFITS. — According  to  the  Yearbooks  of  the  De- 
partment of  Agriculture,  the  average  yield  of  potatoes  in  the 
United  States  for  the  10-year  period  1900-1909  inclusive,  was  91 
bushels  per  acre.  In  the  16  western  states,  however,  the  yield 
was  about  150  bushels  and  if  it  were  possible  to  determine  the 
average  yield  on  irrigated  fields  alone  it  would  doubtless  be 
found  to  be  still  higher.  Yields  of  from  300  to  600  bushels  per 
acre  are  not  uncommon. 

The  price  of  potatoes  fluctuates  considerably  from  year  to  year 
and  at  different  times  of  the  year.  The  average  farm  price  per 
bushel  on  December  1,  1910,  was  55.7  cents,  on  the  same  date 
in  1911  it  was  79.9  and  again  in  1912  it  was  50.5  cents.  Taking 
the  country  as  a  whole,  this  rise  and  fall  in  price  is  directly  pro- 
portional to  the  production.  The  profit  from  this  crop  is  there- 
fore a  matter  of  considerable  uncertainty  and  especially  is  this 
true  in  small  isolated  valleys  located  at  a  distance  from  large 
markets.  No  attempt  will  be  made  here  to  state  the  net  profits 
from  the  growing  of  potatoes  more  than  to  say  that  if  the  irriga- 
tion farmer  will  use  care  in  the  selection  of  seed  and  in  the  plant- 
ing, cultivating  and  irrigating  of  his  crop,  he  will  find  that  it  will 
add  materially  to  his  cash  revenues  3  years  out  of  every  4. 
His  chief  concern  should  be  to  increase  the  quantity  and  improve 


204  USE  OF  WATER  IN  IRRIGATION 

the  quality  of  his  output  and  a  careful  application  of  the  principles 
laid  down  in  the  foregoing,  together  with  a  study  of  the  best  prac- 
tice in  the  community,  will  do  much  to  accomplish  this  aim. 

SUGAR  BEETS 

The  growing  of  sugar  beets  is  subject  to  conditions  unlike  those 
for  any  other  crop.  Owing  to  their  bulk,  sugar  beets  can  not  be 
shipped  a  long  distance  and  it  is  therefore  necessary  that  they  be 
grown  near  a  sugar  factory.  On  the  other  hand  the  factory  must 
be  assured  that  a  large  enough  acreage  is  planted  to  sugar  beets 
each  year  to  keep  the  plant  running  sufficiently  long  to  make  the 
enterprise  profitable.  The  grower  and  the  sugar  company  are 
therefore  interdependent. 

Sugar  beet  factories  have  capacities  ranging  from  400  to  1200 
tons  of  beets  daily  and  the  " campaign"  or  time  the  factory  runs 
is  from  80  to  120  days,  varying  with  the  locality  and  the  season. 

Each  sugar  beet  grower  is  required  to  enter  into  a  contract  with 
the  factory  before  the  beginning  of  the  crop-growing  season. 
These  contracts  provide  that  the  grower  shall  prepare  the  area 
which  is  to  be  devoted  to  beets  in  a  thorough  manner  and  that 
the  seed  will  be  planted  and  the  beets  grown,  blocked,  thinned, 
harvested  and  delivered  in  accordance  with  instructions  and  under 
the  supervision  of  duly  authorized  agents  or  field  superintendents 
of  the  company.  The  company  agrees  to  commence  receiving 
beets  as  soon  as  they  are  matured.  Instructions  are  given  in  the 
contracts  regarding  the  harvesting,  marketing  and  siloing  of  the 
crop.  The  company  agrees  to  furnish  the  seed  and  do  the  plant- 
ing at  specified  prices  per  pound  and  per  acre,  respectively.  It 
is  usually  specified  that  the  beets  shall  be  of  80  per  cent,  purity 
and  contain  12  per  cent,  of  sugar  or  more.  The  price  per  ton 
for  beets  meeting  the  requirements  in  the  contract  is  also  stated 
and  an  additional  50  cents  is  paid  for  siloed  beets.  Not  over 
25  per  cent,  of  the  crop  is  allowed  to  be  siloed  and  this  only  upon 
the  request  of  the  company.  The  growers  are  privileged  to 
employ  a  man  at  their  own  expense  satisfactory  to  the  company, 
to  check  the  tare  and  weights  of  the  beets  or  the  beet  polarization 
of  the  laboratory.  Settlement  is  made  on  or  about  the  tenth  of 
each  month  for  all  beets  received  during  the  first  half  of  the  pre- 


IRRIGATION  OF  STAPLE  CROPS  205 

ceding  month  and  on  the  twentieth  for  the  last  half  of  the  pre- 
ceding month. 

Sugar  beets  are  grown  successfully  on  almost  all  classes  of  soil 
from  heavy  black  adobe  to  sandy  and  silt  loams.  The  heavy 
soils  are  of  course  harder  to  cultivate  but  if  properly  handled 
such  soils  will  produce  a  large  tonnage  of  beets  high  in  sugar 
content. 

According  to  investigations  conducted  by  the  Bureau  of 
Chemistry  a  number  of  years  ago,  a  climate  with  a  mean  summer 
temperature  of  70  degrees  F.  is  best  for  sugar  beets.  They  grow 
luxuriantly  in  warm  climates  but  the  sugar  content  is  very  low 
while  in  colder  climates  the  growing  season  is  too  short.  It  is  also 
essential  that  there  be  an  absence  of  rain  at  the  time  of  harvest, 
since  a  season  of  wet  weather  near  the  time  of  harvest,  will  cause 
a  renewal  of  growth  which  reduces  the  sugar  content  of  the  beet. 
This  is  one  thing  which  makes  the  West  the  ideal  section  for  sugar 
beet  culture  since  the  water  can  be  applied  or  withheld  at  will. 

Rotation  of  crops  is  just  as  essential  in  the  growing  of  sugar 
beets  as  with  other  crops.  One  instance  is  recorded  where  a 
field  was  cropped  to  sugar  beets  for  7  successive  years  with 
the  result  that  the  tonnage  was  reduced  from  33  to  14  tons  per 
acre.  The  most  common  rotation  is  to  follow  beets  with  grain, 
then  alfalfa,  then  potatoes  or  other  cultivated  crop  and  back  to 
beets  again.  Beets  should  not  be  grown  more  than  3  years 
in  succession  and  2  is  preferable. 

PREPARATION  OF  SOIL  AND  SEEDING. — In  preparing  a  field  for 
seeding,  deep  fall  plowing  (10  to  12  inches)  is  generally  considered 
very  essential.  Except  in  California  it  is  thought  best  to  allow 
the  field  to  remain  in  its  rough  condition  so  as  to  catch  the 
snow  and  to  allow  the  soil  to  be  thoroughly  aerated.  In  early 
spring  it  is  double-disked,  irrigated  if  necessary  and  replowed  to  a 
depth  of  3  or  4  inches.  After  this  second  plowing  the  ground 
should  be  harrowed  down  to  a  fine  seed  bed.  This  last  is  very 
important  since  the  beet  is  a  tender  plant  at  first  and  needs  every 
possible  encouragement  to  develop  its  root  system. 

The  seeding  is  usually  done  by  the  sugar  company,  the  company 
furnishing  the  seed  and  doing  the  seeding  at  prices  stated  in  the 
contract.  An  ordinary  four-row  force-feed  beet  drill  is  used,  15 
to  25  pounds  of  seed  being  sown  per  acre.  The  seed  is  planted  1 


206  USE  OF  WATER  IN  IRRIGATION 

to  2  inches  deep,  and  the  rows  are  spaced  16  to  20  inches  apart  or 
they  may  be  alternately  16  and  24  inches  apart.  The  time  of 
seeding  in  California  extends  from  the  end  of  October  to  May.  In 
most  other  sections  of  the  West  the  time  is  from  April  10  to  May 
20.  Sometimes  rain  falls  before  the  beets  have  sprouted  and  a 
crust  forms.  This  crust  must  be  broken  and  the  usual  methods 
are  to  harrow  the  ground  with  the  teeth  of  the  harrow  slanting 
back  or  to  use  a  corrugated  roller.  In  Farmers'  Bui.  392  it  is 
stated:  " Seemingly  the  best  way  is  to  use  'spiders'  on  a  beet 
cultivator.  .  .  .  The  sharp  points  of  the  implement  prick  into 
and  break  up  the  crust  without  otherwise  disturbing  the  top  soil." 

CARE  OF  THE  YOUNG  PLANTS. — In  caring  for  the  young  plants 
there  are  a  number  of  operations  necessary  in  addition  to  frequent 
cultivations  with  horse  cultivators.  The  first  of  these  is  called 
blocking  and  thinning.  The  blocking  is  done  with  a  hoe  by  cut- 
ting out  part  of  the  young  plants,  leaving  the  remainder  in  bunches 
8  inches  to  1  foot  apart  from  center  to  center.  All  but  one  plant 
in  each  bunch  are  then  removed  by  hand.  This  gives  the  beet 
sufficient  room  to  grow  to  a  desirable  size.  Beets  weighing  1  to 
3  pounds  are  preferable.  This  work  is  usually  done  by  contract 
and  often  small  plants  which  should  have  been  pulled  are  over- 
looked and  these  are  removed  at  the  second  hoeing  which  follows 
in  about  10  days.  A  third  hoeing  is  usually  necessary  following  the 
first  irrigation  which  consists  chiefly  of  cutting  out  or  pulling  the 
large  weeds  which  are  missed  by  the  cultivator.  A  cultivation 
should  follow  each  hoeing  and  each  irrigation  but  this  is  not  done 
in  some  localities.  In  Colorado  very  few  growers  cultivate  after 
irrigation  begins.  However,  since  the  cost  per  acre  for  each  culti- 
vation is  not  more  than  35  or  40  cents,  the  benefits  of  cultivating 
after  each  irrigation  are  more  than  worth  the  additional  expense. 

IRRIGATION. — As  with  other  row  crops,  it  is  very  important  that 
a  field  intended  for  beets  be  carefully  leveled  to  a  uniform  slope 
before  the  crop  is  planted.  The  benefits  from  such  a  course  will 
be  felt  as  long  as  the  land  is  farmed.  If  there  are  irregularities 
in  the  field,  part  of  the  crop  will  suffer  from  lack  of  water  and 
other  parts  will  get  too  much  and  it  will  be  impossible  to  con- 
fine the  water  to  the  furrows. 

The  furrow  method  is  used  almost  exclusively  in  all  western 
states  except  California  and  Kansas.  In  these  latter  states 


IRRIGATION  OF  STAPLE  CROPS  207 

flooding  in  checks  or  borders  is  practised.  This  is  due  to  the  fact 
that  winter  irrigation  is  practised  to  a  great  extent,  most  of  the 
water  being  applied  before  the  crop  is  planted.  Slip  joint  pipe 
is  also  used  in  parts  of  southern  California,  and  in  the  neighbor- 
hood of  Lewiston,  Utah,  and  southern  Idaho  a  method  of  sub- 
irrigation  is  practised.  These  methods  are  the  same  for  sugar 
beets  as  for  other  crops  and  have  been  described  elsewhere  in  this 
volume. 

Where  furrow  irrigation  is  employed  the  furrows  are  made  with 
a  furrowing  sled  or  with  a  cultivator,  using  the  furrowing  shovels 
and  fenders.  The  furrowing  sled  is  a  homemade  device  and  is 
described  in  Farmers'  Bulletin  392  as  follows:  "It  is  made  of  6 
by  6  inch  timbers  42  inches  long  as  runners  and  spaced  wide 
enough  to  straddle  two  rows.  These  timbers  are  set  to  run  on 
edge  and  are  sharpened  at  the  forward  point  and  armed  with  old 
furrowing  shovels  which  about  fit  them.  The  runners  are  securely 
spiked  together  at  the  back  end  with  2-inch  boards  upon  which 
the  driver  rides  and  are  connected  in  front  by  a  4  by  4  inch  timber 
to  which  the  draft  is  attached."  While  this  implement  makes  a 
smooth  furrow  and  is  inexpensive  it  is  not  used  very  extensively 
because  of  the  time  required  to  make  the  furrows  in  this  manner. 

The  furrows  receiving  water  from  one  supply  ditch  should  not 
exceed  500  feet  in  length  and  300  feet  would  be  better  in  most 
cases.  Cross  ditches  should  therefore  be  constructed  at  intervals 
of  300  to  500  feet  at  right  angles  with  the  beet  rows  for  all  ordi- 
nary slopes.  These  consist  simply  of  furrows  made  with  a  single 
or  double  mouldboard  plow.  Water  is  supplied  to  the  furrows  in 
much  the  same  way  as  described  for  the  irrigation  of  potatoes. 

Irrigation  should  be  deferred  as  long  as  possible  in  order  to  en- 
courage the  roots  to  strike  deep  into  the  soil.  If  water  is  applied 
too  soon  it  is  apt  to  result  in  an  over-development  of  the  tops  at 
the  expense  of  the  roots.  Water  should  only  be  supplied  as  needed 
throughout  the  growing  season.  From  2  to  4  applications  are 
usually  sufficient.  Beet  tops  may  wilt  during  hot  days  even 
when  the  ground  is  abundantly  supplied  with  moisture  but  if  they 
still  appear  wilted  in  the  early  morning  it  is  a  sign  that  they  are  in 
need  of  water.  The  ground  should  never  be  allowed  to  become 
dry  enough  to  check  the  vigorous  growth  of  the  beets.  Irrigation 
should  be  discontinued  long  enough  before  harvest  to  allow  beets 


208  USE  OF  WATER  IN  IRRIGATION 

to  mature.  This  is  usually  4  to  6  weeks  but  the  grower  must  use 
his  best  judgment  in  this  matter  combined  with  an  observance  of 
the  practice  of  the  most  successful  growers  in  the  community. 

Some  difference  of  opinion  exists  as  to  the  relative  merits  of 
night  and  day  irrigation.  Those  who  advocate  day  irrigation 
claim  that  they  can  control  the  water  better  in  the  day  time  and 
thus  insure  a  more  even  distribution  and  less  waste.  The  ad- 
vantages of  night  irrigation  are  that  water  will  go  farther  at  night 
due  to  less  evaporation,  that  the  temperature  of  the  water  is 
higher  and  that  there  is  less  danger  from  scalding.  In  many  sec- 
tions where  a  system  of  rotation  is  practised  irrigators  are  com- 
pelled to  irrigate  both  night  and  day  since  they  are  only  allowed 
to  use  the  water  for  a  stated  period.  Where  night  irrigation  is 
practised  either  from  choice  or  necessity  it  is  of  great  advantage 
to  have  the  field  thoroughly  leveled  and  lath  boxes,  tubes  or  other 
devices  in  the  ditches  to  feed  the  water  to  the  furrows  in  small 
uniform  streams. 

HARVESTING. — The  harvesting  like  the  planting  and  cultivation 
of  sugar  beets,  is  done  under  the  supervision  of  the  sugar  com- 
panies. About  the  time  the  beets  are  maturing  the  field  agents 
of  the  factory  take  a  number  of  beets  from  various  parts  of  the 
field  and  have  them  tested  for  purity  and  sugar  contents.  If 
they  are  found  to  meet  the  requirements,  orders  are  issued  to  the 
grower  to  harvest  the  crop. 

If  the  ground  is  soft  enough  to  permit,  a  beet  puller  is  used  to 
plow  out  the  beets.  This  consists  of  two  prongs  which  run  one  on 
either  side  of  the  row  close  to  the  beets.  This  raises  and  loosens 
the  beets  so  that  they  can  be  easily  freed  from  the  soil.  If  the 
ground  is  hard  a  beet  plow  is  used,  an  implement  somewhat  like 
a  subsoil  plow.  After  these  implements  come  a  crew  of  men  who 
gather  the  beets  into  windrows  or  piles,  cut  off  the  tops  at  the 
point  of  the  lowest  leaf  and  pile  them  up  preparatory  to  hauling 
to  the  dumps  or  factory.  If  the  piles  have  to  be  left  in  the  field 
over  night  the  beet  tops  are  thrown  over  them  to  protect  them 
against  possible  damage  from  frost.  As  rapidly  as  possible  the 
beets  are  hauled  to  the  factory  or  loading  station.  Sometimes 
it  is  impossible  to  get  cars  fast  enough  to  take  care  of  the  beets 
as  they  come  in  and  provision  is  usually  made  in  the  contracts 
for  piling  beets  at  the  loading  station  until  cars  can  be  obtained. 


IRRIGATION  OF  STAPLE  CROPS  209 

SILOING. — In  the  Rocky  Mountain  States  it  is  not  possible  usu- 
ally for  the  factory  to  take  care  of  the  entire  crop  at  the  time  of 
harvest  and  it  becomes  necessary  to  store  or  silo  a  part  of  the 
crop  until  such  time  as  the  factory  can  receive  them.  This  con- 
sists simply  of  piling  the  beets  carefully,  the  piles  averaging  from 
1000  to  2000  pounds  each,  and  covering  them  with  a  6  to  12-inch 
layer  of  dirt,  leaving  a  small  space  at  the  top  for  ventilation. 
As  previously  stated,  50  cents  additional  is  paid  for  siloed  beets 
to  compensate  for  the  additional  labor. 

COST  OF  GROWING. — Farmers'  Bui.  392  itemizes  the  cost  of 
growing  sugar  beets  as  follows: 

Plowing  land  10  to  12  inches  deep $3 .00 

Harrowing,  leveling,  cultivating,  and  preparing  seed 

bed 2.00 

Drilling  in  seed 0.50 

20  pounds  seed 2 . 00 

Cultivating  five  times  at  40  cents 2 . 00 

Furrowing  twice 1 . 00 

Irrigating  three  times — labor 3 . 00 

Thinning,  hoeing  and  topping — contract 20 . 00 

Plowing  out 2.00 

Hauling  at  50  cents  per  ton  (17  ton  crop) 8.50 

Water  charge  for  maintenance  of  canals 0.75 


Total $44.75 

YIELDS  AND  PROFITS. — The  average  yield  of  sugar  beets 
throughout  the  arid  region  is  only  about  10  to  12  tons  per  acre. 
With  such  a  yield  the  profit  is  very  small  but  with  proper  care  the 
yield  should  be  much  larger.  Yields  of  15  to  20  tons  are  usually 
obtained  by  successful  growers  and  as  high  as  36  tons  have  been 
recorded.  The  price  per  ton  does  not  fluctuate  as  much  for  this 
crop  as  it  does  for  most  field  crops  so  if  the  grower  gets  a  good 
yield  he  is  practically  assured  of  a  good  profit. 

38.  Irrigation  of  Orchards. — Four  years  ago  the  writer  pre- 
pared an  article  on  this  subject  which  was  published  as  Farmers' 
Bui.  404  of  the  U.  S.  Department  of  Agriculture.  The  more 
important  features  of  this  publication  are  reproduced  in  this 
article,  together  with  such  modifications  and  additional  informa- 
tion as  the  experiences  of  the  past  4  years  seems  to  warrant. 

SELECTION  OF  LAND. — Care  and  good  judgment  should  be  exer- 
cised in  the  selection  of  an  orchard  tract.  If  it  turns  out  well 

14 


210  USE  OF  WATER  IN  IRRIGATION 

the  profits  are  high,  but  if  it  fails  the  losses  are  heavy.  It  in- 
volves the  setting  aside  of  good  land,  the  use  of  irrigation  water 
and  somewhat  heavy  expenses  in  purchasing  trees,  setting  them 
out  and  caring  for  them  until  they  begin  to  bear. 

Assuming  that  the  climate  and  soil  of  the  district  selected  are 
adapted  to  the  kind  of  trees  to  be  grown,  the  next  most  important 
things  to  consider  are  good  drainage  and  freedom  from  early 
and  late  frosts.  Low-lying  lands  under  a  new  irrigation  system 
should  be  regarded  with  suspicion,  even  if  the  subsoil  be  quite 
dry  at  the  time  of  planting.  The  results  of  a  few  years  of  heavy 
and  careless  irrigation  on  the  higher  lands  adjacent  may  render 
the  lowlands  unfit  for  orchards.  On  the  other  hand,  the  higher 
lands  are  not  always  well  drained  naturally.  A  bank  of  clay 
extending  across  a  slope  may  intercept  percolating  water  and 
raise  it  near  the  surface.  Favored  locations  for  orchards  in  the 
mountain  states  are  often  found  in  the  narrow  river  valleys  at 
the  mouths  of  canyons.  The  coarse  soil  of  these  deltas,  the  steep 
slopes,  and  the  daily  occurrence  of  winds  which  blow  first  out  of 
the  canyons  and  then  back  into  them,  afford  excellent  conditions 
for  the  production  of  highly  flavored  fruits  at  the  minimum  risk 
of  being  injured  by  frost. 

Proper  exposure  is  another  important  factor.  In  the  warmer 
regions  of  the  West  and  Southwest  a  northern  exposure  is  some- 
times best,  but  as  a  rule  the  orchards  of  the  West  require  warmth 
and  sunshine,  and  a  southerly  exposure  is  usually  more  desirable. 
Natural  barriers  frequently  intercept  the  sweep  of  cold,  destruc- 
tive winds,  and  when  these  are  lacking,  wind-breaks  may  be 
planted  to  serve  the  same  purpose.  Depressions  or  sheltered 
coves  should  be  avoided  if  the  cold  air  has  a  tendency  to  collect 
in  them,  a  free  circulation  of  air  being  necessary  to  drive  away 
frost.  The  low-lying  lands  seem  to  be  the  most  subject  to  cold, 
stagnant  air. 

While  experience  has  shown  that  orchard  trees  of  nearly  all 
kinds  can  be  successfully  grown  on  soils  that  differ  widely  in  their 
mechanical  and  chemical  composition,  it  has  also  shown  that 
certain  types  of  soils  are  best  adapted  to  particular  kinds  of  trees. 
Thus  the  best  peach,  almond,  apricot,  and  olive  orchards  of  the 
West  are  found  on  the  lighter  or  sandier  loams;  the  best  apple, 
cherry,  and  pear  orchards  on  heavier  loams;  while  walnut,  prune, 


IRRIGATION  OF  STAPLE  CROPS  211 

and  orange  orchards  do  best  on  medium  grades  of  soil.  The 
requirements  of  all,  however,  are  a  deep  rich,  and  well-drained 
soil. 

GRADING  THE  SURFACE. — As  a  rule  fruit  trees  are  planted  on 
lands  previously  cultivated  and  cropped.  One  of  the  best  prepara- 
tory crops  for  orchards  is  alfalfa.  This  vigorous  plant  breaks  up 
the  soil  and  subsoil  by  its  roots,  collects  and  stores  valuable  plant 
foods,  and  when  it  is  turned  under  at  the  end  of  the  second  or 
third  year  leaves  the  soil  in  much  better  condition  for  the  reten- 
tion of  moisture  and  the  growth  of  young  trees. 

An  effort  should  be  made  to  establish  a  fairly  uniform  grade 
from  top  to  bottom  of  each  tract.  This  is  done  by  cutting  off  the 
high  points  and  depositing  the  earth  thus  obtained  in  the  depres- 
sions. The  length  of  the  furrows  should  not  exceed  one-eighth  of 
a  mile  and  in  sandy  soil  they  should  be  shorter.  As  a  rule,  it  is 
not  difficult  to  grade  the  surface  of  an  orchard  so  that  small 
streams  of  water  will  readily  flow  in  furrows  from  top  to  bottom. 

TIME  TO  IRRIGATE. — The  best  orchardists  believe  that  frequent 
examinations  of  the  stem,  branches,  foliage  and  fruit  are  not 
enough.  The  roots  and  soil  should  likewise  be  examined.  The 
advice  of  such  men  to  the  inexperienced  is:  Find  out  where  the 
bulk  of  the  feeding  roots  is  located,  ascertain  the  nature  of  the  soil 
around  them,  and  make  frequent  tests  as  to  the  moisture  which 
it  contains.  In  a  citrus  orchard  of  sandy  loam  samples  are  taken 
at  depths  of  about  3  feet,  and  the  moisture  content  determined 
by  exposing  the  samples  to  a  bright  sun  for  the  greater  part  of  a 
day.  It  is  considered  that  6  per  cent,  by  weight  of  free  water  is 
sufficient  to  keep  the  trees  in  a  vigorous  condition. 

Dr.  Loughridge  of  the  University  of  California,  in  his  experi- 
ments at  Riverside,  Cal.,  in  June,  1905,  found  an  average  of  3.5 
per  cent,  in  the  upper  2  feet  and  anaverageof  6.16percent.  below 
this  level  in  an  orchard  which  had  not  been  irrigated  since  October 
of  the  preceding  year.  It  had  received,  however,  a  winter  rain- 
fall of  about  16  inches.  On  examination  it  was  found  that  the 
bulk  of  the  roots  lay  between  the  first  and  fourth  foot.  These 
trees  in  June  seemed  to  be  merely  holding  their  own.  When 
irrigated  July  7  they  began  to  make  new  growth.  A  few  days 
after  the  water  was  applied  the  percentage  of  free  water  in  the 
upper  4  feet  of  soil  rose  to  9.64  per  cent.  The  results  of  these 


212  USE  OF  WATER  IN  IRRIGATION 

tests  seem  to  indicate  that  the  percentage  by  weight  of  free  mois- 
ture should  range  between  5  and  10  per  cent,  in  orchard  loams. 

Many  fruit  growers  do  not  turn  on  the  irrigation  stream  until 
the  trees  begin  to  show  visible  signs  of  suffering,  as  a  slight  change 
in  color  or  a  slight  curling  of  the  leaves.  In  thus  waiting  for  these 
signals  of  distress,  both  trees  and  fruit  are  liable  to  be  injured. 
On  the  other  hand,  the  man  who  ignores  these  symptoms  and 
pours  on  a  large  quantity  of  water  whenever  he  can  spare  it,  or 
when  his  turn  comes,  is  apt  to  cause  greater  damage  by  an  over- 
dose of  water. 

APPLYING  WATER. — Orchards  are  irrigated  for  the  most  part 
from  furrows.  The  manner  in  which  water  is  distributed  from  head 
ditches  or  pipes  to  furrows  and  the  location,  spacing  and  depth  of 
furrows  were  described  under  Furrow  Irrigation.  Practice  differs 
as  to  the  amount  of  water  which  is  turned  into  each  furrow  and 
the  number  of  hours  it  is  permitted  to  flow. 

In  Southern  California  a  miner's  inch  of  water  (1/50  second- 
foot)  is  usually  allowed  to  run  in  each  furrow  until  the  soil  is 
moistened  to  a  sufficient  depth.  The  heads  used  vary  from  30  to 
60  miner's  inches. 

In  the  Payette  Valley,  Idaho,  200  or  more  miner's  inches  are 
turned  into  the  head  ditch  and  divided  up  by  means  of  wooden 
spouts  into  a  like  number  of  furrows.  On  steep  ground  much 
smaller  streams  are  used.  The  length  of  the  furrow  varies  from 
300  feet  on  steep  slopes  to  600  feet  and  more  on  flat  slopes.  The 
time  required  to  moisten  the  soil  depends  on  the  length  of  the 
furrow  and  the  nature  of  the  soil.  In  this  locality  it  varies  from  3 
to  36  hours. 

J.  H.  Foreman  owns  20  acres  of  bearing  orchard  under  the 
Sunnyside  Canal  in  the  Yakima  Valley,  Washington,  and  waters 
it  four  times  in  each  season  with  14  miner's  inches  (0.35  cubic 
foot  per  second).  He  makes  three  furrows  between  the  rows, 
which  are  40  rods  long.  The  total  supply  is  applied  to  one-half 
the  orchard  (10  acres)  and  kept  on  48  hours. 

On  the  clayey  loams  of  the  apple  orchards  on  the  east  bench  of 
the  Bitter  Root  River,  Montana,  Prof.  R.  W.  Fisher  has  found,  as 
a  result  of  experimenting,  that  it  requires  from  12  to  18  hours  to 
moisten  the  soil  in  furrow  irrigation  4  feet  deep  and  3  feet  side- 
ways. 


IRRIGATION  OF  STAPLE  CROPS  213 

In  1908  Mr.  Struck,  of  Hood  River,  Oregon,  irrigated  3  acres 
of  apple  trees  in  furrows  360  feet  long,  spaced  3  feet  apart.  About 
a  miner's  inch  of  water  was  turned  into  each  alternate  furrow  from 
a  wooden  head  flume  and  kept  on  for  about  48  hours.  After  the 
soil  had  become  sufficiently  dry  it  was  cultivated,  and  in  8  or  10 
days  thereafter  water  was  turned  into  the  alternate  rows,  which 
were  left  dry  during  the  first  irrigation. 

In  irrigating  the  deciduous  orchards  in  the  Sierra  foothills  of 
Placer  County,  Cal.,  very  small  heads  are  required  in  order  to 
prevent  erosion  on  the  steep  slopes.  The  continuous  flow  of  3  to 
4  miner's  inches  is  sufficient  for  a  20-acre  orchard  during  the  irri- 
gation season  which  extends  from  May  1  to  October  1.  As  a 
rule,  there  is  but  one  furrow  for  each  row  of  trees.  This  may  ex- 
tend down  the  steepest  slope  encircling  the  upper  half  of  each 
tree  in  its  course  or  it  may  extend  in  a  diagonal  direction.  A  tiny 
stream  no  larger,  on  steep  slopes,  than  a  pencil  is  permitted  to 
run  for  24  to  48  hours  and  is  then  changed  to  another  furrow. 

NUMBER  OF  IRRIGATIONS. — For  nearly  half  the  entire  year  the 
fruit  trees  of  Wyoming  and  Montana  have  little  active,  visible 
growth,  whereas  in  the  citrus  districts  of  California  and  Arizona 
the  growth  is  continuous.  A  tree  when  dormant  gives  off  mois- 
ture, but  the  amount  evaporated  from  both  soil  and  tree  in  winter 
is  relatively  small,  owing  to  the  low  temperature,  the  lack  of 
foliage,  and  feeble  growth.  A  heavy  rain  which  saturates  the 
soil  below  the  usual  covering  of  soil  mulch  may  take  the  place  of 
one  artificial  watering,  but  the  light  shower  frequently  does  more 
harm  than  good.  The  number  of  irrigations  likewise  depends  on 
the  capacity  of  the  soil  to  hold  water.  If  it  readily  parts  with  its 
moisture,  light  but  frequent  applications  will  produce  the  best 
results,  but  if  it  holds  water  well  a  heavy  application  at  longer  in- 
tervals is  best,  especially  when  loss  by  evaporation  from  the  soil 
is  prevented  by  the  use  of  a  deep  soil  mulch. 

In  the  Yakima  and  Wenatchee  fruit-growing  districts  of  Wash- 
ington the  first  irrigation  is  usually  given  in  April  or  early  in  May. 
Then  follow  three  to  four  waterings  at  intervals  of  20  to  30  days. 
At  Montrose,  Colorado,  water  is  used  three  to  five  times  in  a 
season.  At  Payette,  Idaho,  the  same  number  of  irrigations  is 
applied,  beginning  about  June  1  in  ordinary  seasons  and  repeating 
the  operation  at  the  end  of  30-day  intervals.  As  a  rule,  the 


214  USE  OF  WATER  IN  IRRIGATION 

orchards  at  Lewiston,  Idaho,  are  watered  three  times,  beginning 
about  June  15.  From  two  to  four  waterings  suffice  for  fruit  trees 
in  the  vicinity  of  Boulder,  Colo.  The  last  irrigation  is  given  on  or 
before  September  5,  so  that  the  new  wood  may  have  a  chance  to 
mature  before  heavy  freezes  occur.  In  the  Bitter  Root  Valley, 
Montana,  young  trees  are  irrigated  earlier  and  of  tener  than  mature 
trees.  Trees  in  bearing  are,  as  a  rule,  irrigated  about  July  15, 
August  10,  and  August  20  of  each  year.  In  San  Diego  County, 
Cal.,  citrus  trees  are  watered  six  to  eight  times,  and  deciduous 
trees  three  to  four  times  in  a  season.  In  Placer  County,  Cal., 
deciduous  trees  are  watered  every  2  weeks. 

DUTY  OF  WATER. — The  duty  of  water  for  1  acre  as  fixed  by  water 
contracts  varies  all  the  way  from  one-fortieth  to  one  four-hun- 
dredth of  a  cubic  foot  per  second.  In  general,  the  most  water 
is  applied  in  districts  that  require  the  least.  Wherever  water  is 
cheap  and  abundant  the  tendency  seems  to  be  to  use  large  quan- 
tities, regardless  of  the  requirements  of  the  fruit  trees.  In  Wy- 
oming the  duty  of  water  is  seldom  less  than  at  the  rate  of  a 
cubic  foot  per  second  for  70  acres.  In  parts  of  southern  Cali- 
fornia the  same  quantity  of  water  not  infrequently  serves  400 
acres,  yet  the  amount  required  by  the  fruit  trees  of  the  latter 
locality  is  far  in  excess  of  that  of  the  former. 

In  recent  years  the  tendency  all  over  the  West  is  toward  a  more 
economical  use  of  water,  and  even  in  localities  where  water  for 
irrigation  is  still  reasonably  low  in  price  it  is  rare  that  more  than 
21/2  acre-feet  per  acre  are  applied  in  a  season.  This  is  the  duty 
provided  for  in  the  contracts  of  the  Bitter  Root  Valley  Irrigation 
Company,  of  Montana,  which  has  40,000  acres  of  fruit  lands  under 
ditch.  Since,  however,  the  water  user  is  not  entitled  to  receive 
more  than  one-half  of  an  acre-foot  per  acre  in  any  one  calendar 
month,  it  is  only  when  the  growing  season  is  long  and  dry  that 
he  requires  the  full  amount. 

In  the  vicinity  of  Boulder,  Colo.,  the  continuous  flow  of  a  cubic 
foot  per  second  for  105  days  serves  about  112  acres  of  all  kinds  of 
crops.  This  amount  of  water,  if  none  were  lost,  would  cover 
each  acre  to  a  depth  of  1.9  feet.  In  other  words,  the  duty  of 
water  is  a  trifle  less  than  2  acre-feet  per  acre. 

In  1908,  the  depth  of  water  used  on  a  21  1/2-acre  apple  orchard 
at  Wenatchee,  Wash.,  was  measured  and  found  to  be  23  inches. 


IRRIGATION  OF  STAPLE  CROPS 


215 


The  trees  were  7  years  old  and  produced  heavily.  This  orchard 
wa-  watered  five  times,  the  first  on  May  13  and  the  last  on  Sep- 
tember 23.  In  San  Diego  County,  Cal.,  1  miner's  inch  (1/50 
second-foot)  irrigates  from  6  to  7  acres  near  the  coast  where  the 
air  is  cool  and  evaporation  low,  but  20  miles  or  so  inland  the  same 
amount  of  water  is  needed  for  about  4  acres. 

On  the  sandy  loam  orchards  of  Orange  County,  Cal.,  it  has  been 
demonstrated  that  2  acre-inches  every  60  days  are  sufficient  to 
keep  bearing  trees  in  good  condition.  The  rainfall  in  this  locality 


0.4 


0.2 


0.2 


O.i 


0.0 


Jan. 


Apr. 


May 


July 


Aug. 


Sept. 


Nov. 


FIG.  67. — Average  duty  of  water  per  month  under  Riverside  Water  Com- 
pany, Dec.  1,  1901,  to  Nov.  30,  1908. 

averages  somewhat  less  than  12  inches  per  annum,  but  about  95 
per  cent,  of  the  total  falls  between  November  and  May,  inclusive. 
The  most  reliable  and  in  many  ways  the  most  valuable  records 
pertaining  to  duty  of  water  on  orchards  have  been  obtained  by 
the  water  companies  of  Riverside  County,  Cal.  Here  more  or 
les.s  irrigation  water  is  used  every  month  of  the  year.  Fig.  67  is 
a  graphic  representation  of  the  average  amount  of  water  used  per 
month  in  a  period  of  7  years  by  the  Riverside  Water  Company 
in  irrigating  about  9000  acres,  of  which  nearly  6000  acres  are 
planted  to  oranges  and  the  balance  to  alfalfa.  The  figures  given 


216 


USE  OF  WATER  IN  IRRIGATION 


in  the  diagram  represent  depth  in  feet  over  the  surface  watered. 
In  the  following  table  is  given  the  average  duty  of  water  per 
month  in  acre-feet  per  acre  under  the  same  system  from  Decem- 
ber 1,  1901,  to  November  30,  1908,  a  period  of  7  years.  The 
table  also  includes  the  average  monthly  rainfall  at  Riverside,  CaL, 
for  the  same  period  and  adding  the  quantity  of  water  applied  in 
irrigation  in  any  one  month  to  the  rainfall  of  that  month  gives 
the  total  moisture  received  by  the  soil. 

TABLE  No.  32 
Water  used  under  Riverside  Water  Company's  System,  1901-1908 


Month 

Average 
depth 
per  acre, 
feet 

Average 
rainfall, 
feet 

Total 
water 
applied, 
feet 

Month 

Average 
depth 
per  acre, 
feet 

Average 
rainfall, 
feet 

Total 
water 
applied, 
feet 

December  . 

0.159 

0.109 

0.268 

July  .  . 

0.272 

0.002 

0.274 

January  .  .  . 
February  .  . 
March  .... 
April  

0.123 
0.046 
0.078 
0.177 

0.170 
0.190 
0.316 
0.068 

0.293 
0.236 
0.394 
0.245 

August.  .  .  . 
September  . 
October  ... 
November  . 

0.269 
0.243 
0.189 
0.169 

0.015 
0.043 
0.073 

0.269 
0.258 
0.232 
0.242 

May  
June  ' 

0.291 
0.274 

0.023 
0.003 

0.314 
0.277 

Total  

2.29 

1.01 

3.30 

INTERCROPPING. — The  large  majority  of  Calif ornia  fruit  growers 
do  not  grow  marketable  crops  between  the  trees.  They  believe 
in  clean  culture,  except  where  leguminous  crops  are  used  to  reno- 
vate and  fertilize  the  soil.  From  the  standpoint  of  the  large 
commercial  orchard  and  the  well-to-do  proprietor,  this  practice 
has  much  to  recommend  it.  The  planting  of  such  an  orchard  is 
regarded  as  a  long-time  investment.  Little,  if  any,  returns  are 
expected  for  the  first  few  years,  but  when  the  trees  approach 
maturity,  and  are  in  full  bearing  the  anticipated  profits  are  sup- 
posed to  compensate  the  owner  for  all  the  lean  years.  Any 
treatment,  therefore,  which  tends  to  rob  the  soil  of  its  plant  food 
when  the  trees  are  young  or  to  retard  their  growth  is  pretty  cer- 
tain to  lessen  the  yields  and  the  consequent  profits  in  later  years. 
Prof.  E.  J.  Wickson,  director  of  the  California  Experiment  Sta- 
tion, tersely  expressed  the  prevailing  opinion  on  this  question  in 
California  in  his  work,  "  Calif  ornia  Fruits  and  How  to  Grow 
Them"  in  the  following  language:  "All  intercultures  are  a  loan 
made  by  the  trees  to  the  orchardist.  The  term  may  be  long  and 


IRRIGATION  OF  STAPLE  CROPS  217 

the  rate  of  interest  low,  but  sooner  or  later  the  trees  will  need  res- 
titution  to  the  soil  of  the  plant  food  removed  by  intercropping." 

Mr.  S.  W.  McCulloch,  who  controls  150  acres  of  citrus  orchards 
in  southern  California,  goes  further  in  stating,  "It  is  always 
detrimental  to  the  development  of  an  orchard  to  grow  crops 
between  the  trees.  In  some  cases  the  effect  is  not  marked  aside 
from  securing  less  rapid  growth,  but  it  will  affect  the  crops  of  fruit 
for  several  years  and  in  the  end  nothing  will  be  gained." 

Notwithstanding  all  this,  the  poor  man  must  needs  make  the 
loan  or  his  children  may  starve.  The  settler  on  a  small  tract 
set  out  to  young  trees  cannot  afford,  if  his  means  are  limited,  to 
wait  4  or  5  years  for  the  first  returns.  He  must  produce  crops 
between  the  rows,  and  the  question  for  him  to  consider  is 
how  this  can  be  done  with  the  least  possible  injury  to  the  trees. 
A  plentiful  supply  of  water  and  a  deep  rich  soil  are  the  essentials 
of  intercropping.  In  districts  that  depend  on  a  meager  rainfall 
of  15  to  20  inches  per  annum,  or  where  irrigation  water  is  both 
scarce  and  costly,  the  practice  becomes  of  doubtful  -value  under 
any  circumstances.  In  most  of  the  fruit  districts  of  the  West 
water  for  irrigation  is  still  reasonably  low  in  price,  and  the  extra 
amount  required  for  intercropping  represents  but  a  small  part  of 
the  net  gains  from  such  crops. 

Shallow-rooted  plants  are  considered  the  most  desirable  for 
this  purpose.  Squash,  melons,  sweet  potatoes,  tomatoes,  and 
peanuts  are  the  most  common  in  California.  The  cultivation  is 
done  with  one  horse  and  a  small  cultivator.  A  clear  space  3  to 
4  feet  wide  is  left  on  each  side  of  the  young  trees.  In  the  Verde 
River  Valley  of  Arizona,  strawberries,  lettuce,  onions,  and  melons 
are  raised  in  the  young  orchards.  In  parts  of  Idaho,  alfalfa 
fields  are  frequently  plowed  under  to  plant  trees.  When  this  is 
done,  berries,  beans,  melons,  onions,  and  tomatoes  can  be  grown 
between  the  rows  for  several  years  without  any  apparent  injury 
to  young  trees.  In  northern  Colorado,  raspberries,  goose- 
berries, currants,  as  well  as  corn,  beans,  and  peas  are  often  planted 
in  orchards,  while  in  southwestern  Kansas  the  order  is  usually 
cabbage,  melons  and  sweet  potatoes. 

In  the  young  apple  orchards  of  Hood  River  Valley,  Oregon, 
strawberries  are  frequently  planted  between  the  rows.  The 
manner  in  which  this  is  done,  as  well  as  the  system  of  contour 


218 


USE  OF  WATER  IN  IRRIGATION 


planting  which  is  there  practised,  is  shown  in  Fig.  68.  The 
manager  of  a  large  apple  orchard  company  in  Montana  states 
that  no  appreciable  effect  is  noticed  on  apple  trees  as  a  result  of 
growing  potatoes,  cabbage,  beans,  onions,  and  other  vegetables 
between  the  trees  providing  the  intercrops  are  well  cultivated 
and  irrigated.  In  the  fruit  districts  of  Washington,  intercropping 
is  a  common  practice.  In  1907  a  fruit  grower  raised  in  10  acres 
of  two-year-old  trees  cantaloupes,  tomatoes,  peppers,  cucumbers, 
corn,  radishes,  beans,  peas,  potatoes,  and  turnips,  all  of  which 
netted  him  $2,086.50,  or  an  average  of  $208.65  an  acre. 


FIG.  68. — Orchard  showing  strawberries  between  rows  of  trees. 

While  opinions  differ  regarding  the  wisdom  of  growing  such 
crops  as  have  been  named  between  the  tree  rows,  most  fruit  grow- 
ers are  convinced  of  the  beneficial  effects  of  cover  crops.  Not- 
withstanding the  scarcity  and  high  value  of  water  in  the  River- 
side citrus  district,  the  superintendent  of  a  large  fruit  company 
has  for  years  grown  peas  and  vetch  in  the  orange  and  lemon 
orchards  under  his  management,  and  advocates  the  free  use  of 
irrigation  water  to  supplement  the  winter  rains  for  the  rapid  and 
vigorous  growth  of  such  crops.  In  the  walnut  groves  of  Orange 


IRRIGATION  OF  STAPLE  CROPS  219 

County,  Cal.,  bur  clover  is  sown  in  the  fall,  given  one  or  two 
irrigations  during  the  winter  if  the  rainfall  is  below  the  normal 
and  plowed  under  in  April. 

The  cost  of  such  cover  crops  as  peas,  vetch,  or  clover  includes 
the  seed,  the  labor  of  sowing  it,  the  water,  and  the  time  required 
to  apply  it.  These  items,  according  to  Dr.  S.  S.  Twombly,  of 
Fullerton,  Cal.,  amount  to  from  $2.50  to  $3.25  per  acre.  Twenty 
tons  per  acre  of  green  material  is  perhaps  an  average  crop.  In 
this  tonnage  there  would  be  about  160  pounds  of  nitrogen,  which 
at  20  cents  per  pound  represents  a  value  of  $32  per  acre  for  a  cover 
crop  like  vetch. 

Other  beneficial  effects  of  cover  crops  are  quite  fully  sum- 
marized by  Prof.  W.  S.  Thornber,  horticulturist  of  the  Washing- 
ton Agricultural  Experiment  Station  (Wash.  Sta.  Pop.  Bui.  8). 

WINTER  IRRIGATION. — When  water  is  used  outside  of  the  regular 
irrigation  period,  or  what  is  in  many  cases  equivalent,  outside 
of  the  growing  season,  it  is  termed  winter  irrigation.  Over  a 
large  part  of  the  arid  region  the  growing  season  is  limited  by  low 
temperatures  to  150  days,  or  less,  and  when  the  flow  of  streams 
is  utilized  only  during  this  period  much  valuable  water  runs  to 
waste. 

It  was  for  the  purpose  of  utilizing  some  of  this  waste  that  the 
orchardists  of  the  Pacific  Coast  States  and  Arizona  began  the 
practice  of  winter  irrigation.  The  precipitation  usually  occurs 
in  winter  in  the  form  of  rain,  and  large  quantities  of  creek  water 
are  then  available.  This  water  is  spread  over  the  orchards  in 
January,  February,  and  March,  when  deciduous  trees  are  dor- 
mant. The  most  favorable  conditions  for  this  practice  are  a 
mild  winter  climate;  a  deep,  retentive  soil  which  will  hold  the, 
greater  part  of  the  water  applied;  deep-rooted  trees;  and  a  soil 
moist  from  frequent  rains. 

The  creek  water  which  was  applied  to  some  of  the  prune 
orchards  of  the  Santa  Clara  Valley,  California,  during  the  wirter 
of  1904  was  measured  by  the  agents  of  irrigation  investigations 
with  the  following  results:  From  February  27  to  April  23,  1241 
acres  were  irrigated  under  the  Statler  ditch  to  an  average  depth 
of  1.58  feet.  From  February  12  to  April  23,  2021  acres  were 
irrigated  under  the  Sorosis  and  Calkins  ditches  to  an  average 
depth  of  1.75  feet.  In  the  majority  of  cases  the  orchards  which 


220  USE  OF  WATER  IN  IRRIGATION 

are  irrigated  in  winter  in  this  valley  receive  no  additional  supply 
of  moisture  other  than  about  16  inches  of  rain  water. 

In  the  colder  parts  of  the  arid  region  winter  irrigation  is  like- 
wise being  practised  with  satisfactory  results.  The  purpose  is 
not  only  to  store  water  in  the  soil  but  to  prevent  the  winter- 
killing of  trees.  Experience  has  shown  that  it  is  not  best  to 
apply  much  water  to  orchards  during  the  latter  part  of  the  grow- 
ing season,  since  it  tends  to  produce  immature  growth  which 
is  easily  damaged  by  frost.  In  many  of  the  orchards  of  Montana 
no  water  is  applied  in  summer  irrigation  after  August  20.  Owing, 
however,  to  the  prevalence  of  warm  chinook  winds,  which  not 
only  melt  the  snow  in  a  night,  but  rob  the  exposed  soil  of  much 
of  its  moisture,  one  or  two  irrigations  are  frequently  necessary  in 
midwinter. 

39.  Irrigation  of  Rice. — The  total  acreage  devoted  to  rice  grow- 
ing in  the  United  States  in  1912,  was,  according  to  the  Decem- 
ber Crop  Report  of  the  Department  of  Agriculture  for  that 
year  722,800  acres;  the  production  was  25,054,000  bushels  valued 
at  $23,423,000.  The  distribution  of  the  area  in  rice  in  that  year 
was  as  follows: 

Per  cent,  of 
State  Acres 

total 

Louisiana 352,600  48.78 

Texas 265,500  36.73 

Arkansas 90,800  12 . 56 

So.  Atlantic  States 12,500  1 . 73 

California 1,400  0.19 

Total 722,800  99.99 

In  1896,  the  forerunner  of  the  modern  pumping  plant  for  the 
irrigation  of  rice  was  operated  for  the  first  time  near  Crowley, 
Louisiana,  marking  the  beginning  of  a  new  era  in  the  develop- 
ment of  irrigated  rice  in  this  country.  Largely  as  a  result  of 
better  facilities  for  securing  and  controlling  an  adequate  water 
supply,  the  yield  of  cleaned  rice  increased  from  116,000,000 
pounds  in  1897  to  520,000,000  pounds  in  1907. 

During  the  past  5  years  questions  of  water  supply,  canals, 
application  and  duty  of  water,  and  the  effect  of  water  on  rice 
production  have  been  carefully  investigated  by  C.  G.  Haskell  of 
Irrigation  Investigations,  Office  of  Experiment  Stations,  U.  S. 


IRRIGATION  OF  STAPLE  CROPS  221 

Department  of  Agriculture.  The  writer  has  drawn  freely  from 
Mr.  Haskell's  publications  and  acquired  knowledge  on  this  sub- 
ject in  preparing  the  following  article. 

SOIL,  CLIMATE  AND  WATER  SUPPLY. — Practically  all  of  the  rice 
grown  in  the  United  States  is  irrigated,  and  irrigated  rice  to  be 
profitable  requires  the  right  kind  of  soil  and  subsoil,  a  suitable 
climate,  and  an  adequate  water  supply.  Any  rich  loam  or  clay 
soil  that  is  level  enough  to  be  economically  irrigated,  if  underlaid 
with  a  compact  clay  subsoil,  impervious  to  water,  is  suitable  for 
rice  culture.  If  the  land  is  rolling  or  broken,  water  can  not  be 
easily  kept  on  it,  and  if  the  subsoil  is  loose,  there  will  be  such  a 
loss  of  water  that  irrigation  will  be  very  expensive.  Not  more 
than  two  successive  rice  crops  can  be  grown  profitably  on  very 
sandy  loam  soil.  The  crop  must  likewise  have  at  least  4 
months  of  warm  weather  and  no  cool  nights  during  heading  time. 

The  water  used  in  rice  irrigation  is  derived  from  streams,  lakes, 
bayous,  and  wells.  More  than  97  per  cent,  of  the  water  used  is 
pumped  and  over  one-quarter  of  this  is  pumped  from  wells.  A 
very  small  acreage  is  irrigated  with  stored  water  from  wells,  and  a 
similar  area  with  water  stored  in  shallow  reservoirs  and  allowed 
to  flow  to  rice  planted  on  lower  land.  Sometimes  rice  planted 
on  low  land  receives  its  irrigation  from  the  inflow  of  water  from 
surrounding  higher  fields.  This  is  the  so-called  " Providence" 
method.  Along  the  Atlantic  coast  several  thousand  acres  of  rice 
are  grown  on  low  land  near  the  mouths  of  rivers  and  are  irrigated 
by  fresh  river  water  backed  up  over  it  during  high  tides. 

PREPARATION  OF  LAND,  PLANTING  AND  SEEDING. — On  the  prai- 
ries the  land  is  generally  plowed  with  sulky  or  gang  plows.  Along 
the  Mississippi  River  and  the  Atlantic  coast  where  negro  laborers 
do  most  of  the  work  the  walking  plow  is  generally  used.  The  land 
is  disked  and  harrowed  to  make  a  good  seed  bed  and  the  rice  is 
planted  with  a  drill  or  sometimes  with  a  broadcast  seeder.  Along 
the  Atlantic  coast  the  rows  are  made  15  inches  apart  to  allow 
the  rice  to  be  cultivated,  but  in  all  other  sections  rice  is  not 
cultivated  and  the  rows  are  made  about  7  inches  apart. 

In  Louisiana,  Texas  and  Arkansas,  Honduras  and  Shinriki 
(Japan)  rices  are  the  principal  varieties  grown  for  commercial 
purposes,  although  during  the  last  few  years  several  varieties 
have  been  developed  in  this  country  which  do  better  than  the 


222  USE  OF  WATER  IN  IRRIGATION 

imported  rices.  The  Honduras  is  a  tall  rice  with  coarse  stalks 
and  wide  leaves.  The  heads  and  the  grains  in  the  heads  hang 
long  and  are  light  colored.  The  Japan  rice  is  short  with  small 
wire-like  stalks  and  narrow  leaves.  The  head  and  grains  are 
shorter  than  the  Honduras  rice.  By  reason  of  the  large  number 
of  heads  per  plant,  Japan  rice  makes  larger  yields  than  the  Hon- 
duras, but  it  does  not  bring  as  high  a  price  on  the  market.  On 
the  Atlantic  coast  the  famous  Carolina  Gold  Seed  and  white  rice 
are  grown.  The  Gold  Seed  is  about  the  size  of  the  Honduras 
rice  and  is  known  by  the  golden  color  of  the  hulls.  About  90 
pounds  of  Honduras  or  65  pounds  of  Japan  rice  are  generally 
planted  to  the  acre. 

CANALS,  PUMPING  PLANTS,  AND  LATERALS. — The  irrigation 
canals  which  carry  the  water  from  the  streams  and  lakes  to  the 
lands  to  be  irrigated  are  built  on  high  ground  and  sometimes  ex- 
tend 30  miles  from  their  source.  The  larger  canals  are  merely  two 
parallel  levees  built  upon  the  surface  of  the  ground  from  200  to 
275  feet  apart,  and  since  their  grades  are  very  flat  .they  are  really 
long  reservoirs  in  which  water  flows  very  slowly.  The  slow  veloc- 
ity causes  little  loss  of  head  and  keeps  the  total  lift  at  the  pump- 
ing plant  at  a  minimum.  This  is  essential,  for  the  cost  of  the 
water  depends  largely  upon  the  height  to  which  it  is  elevated. 
From  the  main  canals  the  water  is  conveyed  to  the  fields  in 
laterals. 

Some  of  the  largest  and  best  equipped  pumping  plants  in  the 
world  pump  into  irrigation  canals  from  the  streams  of  south- 
western Louisiana  and  southeastern  Texas.  They  are  frequently 
equipped  with  large  horizontal  centrifugal  or  rotary  pumps, 
operated  by  compound  condensing  Corliss  engines.  Steam  is 
generally  supplied  from  horizontal  water-tube  boilers  and  petro- 
leum is  often  used  for  fuel. 

WELLS. — A  large  part  of  the  land  upon  which  rice  is  grown  is 
underlain  with  waterbearing  beds  of  sand  and  gravel  at  depths 
varying  from  40  to  1000  feet.  Great  improvements  have  been 
made  during  recent  years  in  methods  of  drilling  and  equipping 
wells.  Practically  all  of  the  water  obtained  from  wells  is  pumped. 
The  average  of  the  discharges  from  over  800  wells  in  Texas, 
Arkansas,  and  Louisiana  is  950  gallons  per  minute.  Some  wells 
supply  as  high  as  3000  gallons  per  minute  and  irrigate  about 


IRRIGATION  OF  STAPLE  CROPS 


223 


400  acres  of  rice.  Irrigation  water  from  wells  enables  much  land 
to  be  planted  to  rice  which  is  out  of  reach  of  the  river,  bayou  or 
lake  canals  and  could  not  otherwise  be  irrigated.  The  greater 
part  of  the  irrigation  development  in  the  rice  country  during 
recent  years  has  been  along  the  line  of  irrigation  from  wells. 


FIG.  69. — Push  for  building  levees   and  digging  small  drainage   ditches. 

FIELD  LEVEES. — High  levees  are  built  around  the  field  to  pre- 
vent the  escape  of  water.  Other  levees  are  built  across  the  field 
on  contours  to  hold  the  water  on  the  land.  A  contour  field  levee  is 
built  on  the  surface  of  the  ground  for  every  drop  of  three-tenths 
of  a  foot.  Sometimes  the  levees  are  located  on  every  two  or 


FIG.  70. — Cross-section  of  the  common  high  field  levee. 

four-tenths  of  a  foot  drop.  The  field  is  thus  divided  into  irregu- 
lar shaped  cuts  depending  in  size  upon  the  slope  of  the  ground. 
All  the  land  in  each  cut  is  of  nearly  the  same  elevation.  Fig.  69 
shows  a  wooden  " push"  that  is  generally  used  to  build  levees  and 
to  dig  small  drainage  ditches. 


224  USE  OF  WATER  IN  IRRIGATION 

In  the  newer  or  more  up  to  date  rice  farms  the  cross  levees 
are  built  wide  so  that  teams  can  work  them  and  rice  can  be  grown 
upon  them.  Fig.  70  shows  a  cross  section  of  a  common,  narrow, 
high,  field  levee.  Fig.  71  shows  a  cross  section  of  a  low,  wide, 
field  levee. 

STRUCTURES  TO  CONTROL  THE  FLOW  OF  WATER  ON  FIELDS.— 
Drainage  ditches  are  provided  so  that  water  can  be  removed 
from  any  cut,  when  desired.  If  the  soil  is  loose,  sandy  loam, 
wooden  gates  are  placed  in  the  field  levees  to  regulate  the  flow 
of  the  water  and  to  prevent  the  levees  washing  out.  Sometimes 
a  sack  is  placed  so  the  water  can  flow  over  it  to  answer  the  pur- 
pose of  a  gate.  The  lateral  or  small  canal  which  carries  the 
water  supply  should  be  built  along  the  side  of  the  field  so  that 
water  can  be  applied  to  any  cut  without  flooding  those  above  it. 


FIG.  71. — Cross-section  of  the  low,  wide  field  levee. 

If  the  field  is  very  large  and  the  cuts  are  long  the  lateral  should 
be  extended  down  the  slope  dividing  the  cuts  so  that  the  water 
will  not  have  to  flow  too  far  to  reach  the  farther  ends  of  the  cuts. 

SECURING  WATER  FOR  IRRIGATION  ALONG  THE  MISSISSIPPI. — 
Along  the  Mississippi  River  rice  grows  on  alluvial  land  just  over 
the  levees.  When  the  crop  was  first  introduced  into  this  section 
the  planters  cut  the  levees  which  protect  the  land  along  the  river 
from  overflow  to  get  water  to  irrigate  their  rice  or  placed  wooden 
gates  or  iron  pipes  in  the  levees  to  allow  the  water  to  flow  from 
the  river  to  their  fields.  After  several  crevasses  and  overflows 
resulted  from  this  practice,  a  law  was  passed  preventing  the  cut- 
ting of  the  levees.  This  made  it  necessary  to  syphon  the  water 
over  them.  As  long  as  the  river  is  low  the  water  has  to  be 
pumped  into  a  reservoir  built  beside  the  levee,  and  of  sufficient 
height  to  cause  the  water  to  flow  from  it  through  the  syphon 
to  the  field. 

Small  portable  pumping  plants  are  used  to  pump  the  water 


IRRIGATION  OF  STAPLE  CROPS  225 

from  the  river  into  the  reservoirs.  During  the  seasons  when 
the  river  is  high  irrigation  water  is  very  cheap  but  when  the  river 
is  low  it  is  very  expensive.  On  the  Mississippi  River  above 
Baton  Rouge,  Louisiana,  the  fields  are  laid  out  and  irrigated 
in  much  the  same  way  as  on  the  prairie  lands.  Below  Baton 
Rouge  the  older  method  is  still  practised. 

Some  idea  of  the  arrangement  of  field  levees  and  ditches 
in  different  parts  of  the  rice  area  may  be  obtained  from  the 
following  outline: 

The  land  along  the  Mississippi  River  slopes  back  to  the  swamp 
or  low  land.  Parallel  drain  ditches  are  dug  down  this  slope  at 
distances  varying  from  200  to  600  feet  apart.  Levees  are  built 
along  the  sides  of  the  ditches  and  cross  levees  at  right  angles 
to  them  for  every  drop  of  two-  to  five-tenths  of  a  foot  in  the 
surface  of  the  land.  The  cross  levees  thus  range  from  50  to  800 
feet  apart  and  form  rectangular  cuts  of  varying  sizes.  The 
water  is  allowed  to  flow  from  cut  to  cut  across  the  field;  and, 
when  the  field  is  to  be  drained  the  water  is  allowed  to  flow  off 
through  the  drainage  ditches. 

Along  the  Atlantic  Coast  some  of  the  land  near  the  mouths  of 
rivers  influenced  by  tides,  is  level  and  lies  between  high  and 
low  tide.  At  high  tide  the  fresh  water  of  the  river  is  backed 
up  until  it  is  higher  than  the  land.  Large,  high  levees  are  built 
around  the  field  to  hold  the  river  water  from  the  land.  Inside 
field  levees,  generally  straight,  are  built  across  the  field  to  divide 
it  into  cuts  approximately  40  acres  in  size.  A  large  ditch  or 
canal  is  dug  in  from  the  river  and  branches  from  the  canal 
extend  to  each  cut.  Where  the  branch  canals  reach  the  levees 
surrounding  the  cuts  a  wooden  box  with  a  gate  on  each  end  to 
close  it  is  placed  under  the  levees.  The  box  and  gates  together 
are  called  a  "trunk." 

The  gates  are  arranged  so  that  they  can  be  set  to  work  auto- 
matically and  let  the  water  on  or  off  the  field  at  the  change  of 
tide,  whichever  may  be  desired.  A  ditch  about  4  feet  wide 
and  4  feet  deep  runs  from  the  trunk  parallel  to  the  inside 
levees  and  about  20  feet  from  them  around  the  inside  of 
each  cut  and  back  to  the  trunk.  Other  narrow  ditches  con- 
nect with  the  larger  ditches  from  opposite  sides,  leaving  room 
only  -for  a  team  to  pass  between  the  ends.  These  inside  systems 

15 


226  USE  OF  WATER  IN  IRRIGATION 

of  ditches  are  made  to  allow  the  water  to  flow  quickly  to  and 
from  the  fields  while  the  tide  is  high  or  low. 

Rice  is  cultivated  on  the  Atlantic  Coast  only.  In  the  other 
states  the  irrigation  is  not  only  expected  to  supply  the  moisture 
necessary  for  plant  growth  and  to  control  the  pests  which  attack 
young  rice  when  the  land  is  not  flooded,  but  it  is  also  expected  to 
keep  down  the  weeds  and  grasses.  If  there  is  not  enough  mois- 
ture in  the  soil  to  sprout  the  seed,  water  is  applied  just  before 
or  just  after  planting.  It  is  not  allowed  to  stand  long  on  the 
newly  planted  rice,  however,  in  order  that  the  seed  may  not 
rot  in  the  ground.  The  period  of  danger  is  from  the  time  the 
rice  starts  to  sprout  until  it  is  above  the  ground.  If  the  field 
cannot  be  completely  drained,  sprout  flooding  can  not  be  prac- 
tised safely.  The  water  should  then  be  applied  first  and  the 
rice  planted  ag  the  land  dries  or  planting  should  be  delayed  until 
rain  falls. 

If  the  corn  beetles,  wire-worms,  white  grubs,  or  birds  are 
injuring  the  young  rice,  water  is  applied  to  drive  the  pests  away 
even  if  the  rice  is  just  above  the  ground. 

APPLICATION  OF  WATER. — Irrigation  water  is  applied  to  the 
land  when  the  rice  is  4  inches  above  the  surface.  If  the  water 
is  held  deep  when  the  rice  is  young,  it  will  cause  the  plants  to 
grow  tall  and  slender  at  a  rapid  rate  and  not  to  thicken  up  or 
stool  out  to  make  many  heads  to  each  plant.  If  the  weather  is 
very  hot,  the  water  must  be  held  not  less  than  1  inch  and 
preferably  2  inches  deep  or  it  will  become  hot  enough  to  scald 
the  young  rice.  There  is  little  danger  of  the  water  getting  hot 
enough  to  injure  the  early  planted  rice  but  rice  planted  late  in 
the  season  should  be  watched  carefully. 

After  the  rice  has  grown  enough  to  shade  the  water  there 
is  no  danger  of  scalding  and  the  water  may  be  allowed  to  get 
lower  if  desired.  During  cool  weather  the  water  should  be 
held  from  1  to  2  inches  deep  on  the  land  in  order  that  the 
sun  may  warm  it  quickly  in  the  morning  and  the  plants  be  given 
a  chance  to  grow.  After  the  rice  has  stooled  properly  in  shallow 
water  the  water  is  held  at  an  average  of  4  inches  or  more  on  the 
cuts.  The  average  depth  of  water  on  a  cut  is  the  depth  midway 
between  properly  located  contour  levees.  Tests  to  determine 
the  depth  of  water  which  will  cause  the  greatest  yields  have 


IRRIGATION  OF  STAPLE  CROPS  227 

shown  that  for  old,  grassy  fields  the  yields  increase  with  the 
average  depth  of  water  up  to  6  inches  and  probably  beyond. 
It  is  also  true  that  the  increase  in  yield  is  very  slight  for  average 
depths  greater  than  4  inches.  It  is  therefore  not  economical 
to  flood  deeper  because  it  would  require  the  use  of  a  greater 
amount  of  water  and  the  building  of  higher  field  levees.  New 
land  does  not  require  as  deep  flooding  as  old  land. 

RICE  WATER-WEEVIL  OR  RICE  ROOT-MAGGOT. — The  rice  water- 
weevil  resembles  somewhat  in  size,  shape  and  color,  the  weevil 
that  eats  stored  grain  and  is  most  readily  found  when  the  rice 
has  been  flooded  about  2  weeks  and  is  8  to  10  inches  tall.  It 
may  be  found  on  the  leaves  or  stalks  of  the  rice  plants,  or  swim- 
ming in  the  water,  but  does  little  harm  when  eating  on  the 
leaves  of  the  rice.  When  in  the  larva  stage  the  weevils  sometimes 
do  great  injury  by  eating  the  roots  of  the  rice  plants. 

The  rice  maggot,  as  the  rice  larva  is  called  by  the  farmers, 
is  a  small  white  worm  about  one-fourth  to  one-half  of  an  inch 
long  with  corrugations  or  ridges  running  around  it  and  both 
extremities  somewhat  blunt.  Its  head  looks  like  little  more 
than  a  reddish-brown  speck.  A  rice  maggot  is  found  in  wet 
soils  near  the  roots  of  the  rice  plants  but  should  not  be  mistaken 
for  the  larva  of  the  greenhead  fly  which  is  sometimes  found  in 
wet  or  flooded  rice  fields,  since  the  fly  maggot  does  not  injure 
the  rice.  The  fly  maggot  is  generally  larger,  of  a  darker  color 
and  with  sharper  extremities  than  the  rice  maggot. 

If  the  rice  maggots  when  discovered  have  just  begun  to  eat 
the  roots  of  the  rice  plants  and  there  is  a  little  rain  to  prevent 
the  land  drying,  the  water  is  drained  from  the  cuts  and  the  land 
is  allowed  to  dry  until  the  mud  will  not  stick  to  the  shoes  but 
not  so  that  the  ground  cracks.  The  water  is  then  re-applied 
to  the  cuts.  If  the  rice  maggots  have  already  done  much 
injury  and  the  weather  is  cloudy  or  rainy,  or  if  irrigation  water 
is  too  scarce  to  allow  the  water  to  be  drained  from  the  field,  the 
cuts  are  flooded  deep  with  fresh  water.  This  seems  to  remain 
too  cool  for  the  rice  maggots  and  also  helps  the  rice  to  recover 
from  its  injuries. 

After  the  field  has  been  completely  flooded  the  openings 
in  the  field  levees  are  so  placed  that  the  water  will  flow  in  at 
one  end  of  a  cut  and  out  at  the  other,  also  flowing  down  from 


228  USE  OF  WATER  IN  IRRIGATION 

cut  to  cut  across  the  field.  This  causes  the  water  to  circulate 
and  prevents  it  from  becoming  hot  and  stagnant. 

STRAIGHT-HEAD  OR  "BLIGHT." — Straight-head  or  " blight" 
sometimes  causes  great  loss.  This  is  an  unfavorable  growth  of 
the  rice  plant  occurring  when  too  much  of  its  strength  goes  to 
stalks  and  leaves  and  not  enough  to  grain.  It  can  be  recognized 
by  the  tall  stalks  and  dark  green  leaves  during  the  growing 
period  and  by  the  empty  or  partly  filled  heads  which  stand  straight 
up  at  harvest  time. 

This  trouble  seldom  occurs  on  any  but  sandy  loam  soil  which 
has  not  been  planted  to  rice  for  a  year  or  two.  To  remedy  the 
defective  growth  the  water  should  be  drained  from  the  field  just 
before  the  rice  begins  to  joint,  permitting  the  soil  to  aerate 
until  it  is  about  to  crack.  The  field  should  then  be  reflooded 
with  fresh  water.  Rice  planted  on  newly  plowed  prairie  land 
is  most  apt  to  be  injured  by  straight-head,  although  the  danger 
is  not  so  great  after  the  first  year.  Even  one  plowing  will  so 
change  the  condition  of  the  soil  that  there  is  little  danger. 

Water  is  handled  on  the  rice  fields  along  the  Mississippi  River 
in  much  the  same  way  as  further  west.  On  account  of  weeds 
and  grass  on  most  of  the  older  fields,  the  water  is  applied  early 
and  is  held  deep  on  the  land  throughout  the  whole  season. 
Rice  is  not  cultivated  in  this  section  and  the  small  danger  from 
straight-head  on  this  soil  makes  drainage  unnecessary.  More 
water  than  that  used  on  prairie  land  is  generally  required  be- 
cause the  subsoils  are  not  so  compact.  Weeds  and  grass  are 
generally  cut  while  water  is  on  the  ground. 

HANDLING  WATER  ON  ATLANTIC  COAST  RICE  FIELDS. — Along 
the  Atlantic  Coast  the  rice  fields  are  generally  flooded  as  soon  as 
the  rice  is  planted.  This  flooding  is  called  the  "  sprout  flow."  It 
protects  the  grains  from  the  birds  and  causes  the  seed  to  germi- 
nate. The  water  is  allowed  to  remain  on  the  land  6  to  12  inches 
deep  until  little  white  sprouts  one-third  of  an  inch  long  have 
pushed  through  the  hulls  and  caused  the  rice  to  be  " pipped." 
This  generally  requires  3  to  6  days.  The  water  is  then  drained 
off  and  is  not  re-applied  until  the  rice  is  1  to  2  inches  tall  with 
one  point-like  leaf. 

The  second  flooding,  called  the  "point  or  stretch  flow"  over  the 
young  rice  causes  it  to  grow  quickly,  getting  a  start  on  the 


IRRIGATION  OF  STAPLE  CROPS  229 

and  grass  much  of  which  the  water  is  expected  to  kill. 
When  the  rice  has  grown  to  a  height  of  about  6  inches  the  water 
is  nradually  lowered  to  an  average  depth  of  4  inches  and  is  held 
there  for  13  to  30  days,  according  to  the  strength  of  the  soil, 
the  condition  of  the  plants,  and  the  temperature.  Every  week 
or  10  days  the  water  is  drawn  off  and  fresh  water  is  applied. 

The  "stretch  flow"  is  followed  by  a  period  of  "dry  growth" 
which  lasts  from  40  to  50  days.  If  the  weather  is  dry  a  short 
flooding  is  given  during  the  "dry  growth"  period.  During 
this  period  the  rice  is  cultivated  with  horse  plows  2  or  3  times 
and  is  hoed  by  hand  once  or  twice.  All  weeds,  grass,  and  red 
rice  are  uprooted  and  the  ground  is  thoroughly  stirred. 

When  the  plants  have  begun  to  joint  the  "harvest  flow" 
is  turned  on  4  to  5  inches  deep  and  is  allowed  to  remain  until 
just  before  the  rice  is  harvested. 

DUTY  OF  WATER,  RAINFALL,  AND  EVAPORATION. — Measure- 
ments have  been  made  of  rainfall,  evaporation,  and  the  duty  of 
water  for  irrigating  rice  on  prairie  lands  of  Louisiana,  Texas,  and 
Arkansas  for  11  years,  during  which  21  measurements  have 
been  made.  The  averages  of  these  measurements  give  15.74 
inches  of  pumped  water  and  17.16  inches  of  rainfall  applied  to 
the  land  and  a  loss  due  to  evaporation  from  flooded  rice  fields 
of  15.33  inches.  The  total  average  depth  of  water  applied  was 
32.90  inches.  Subtracting  the  evaporation  from  this  leaves 
17.57  inches  which  was  used  by  the  plants,  percolated  into  the 
ground  and  escaped  through  the  outside  field  .levees.  Allow- 
ing time  for  break-down  of  pumping  plant  and  for  stoppage  of 
pumping  when  irrigation  water  is  not  needed  after  rains,  the 
duty  of  water  for  rice  irrigation  for  prairie  land  runs  from  7  1/2 
to  8  gallons  per  minute  per  acre,  depending  upon  the  character 
of  the  land  and  the  distance  the  water  has  to  be  carried  in  the 
canal.  If  the  water  is  pumped  at  the  field  so  there  is  no  loss 
in  a  canal,  less  water  will  be  required.  For  the  black  clay  and 
loam  soils  along  rivers,  like  that  along  the  Mississippi  River, 
10  gallons  of  water  per  minute  per  acre  should  be  provided  while 
if  the  land  has  a  loose  subsoil  and  is  located  near  a  river  or  lake, 
38  to  40  gallons  will  be  needed. 

In  Texas,  Arkansas,  and  all  of  Louisiana,  except  the  strip 
along  the  Mississippi  River  below  Baton  Rouge,  the  water  has 


230  USE  OF  WATER  IN  IRRIGATION 

to  be  drained  from  the  field  in  time  for  the  land  to  become  dry 
enough  to  support  teams  and  binders  at  harvest  time.  This 
requires  from  8  to  14  days  according  to  the  character  of  the  land 
and  the  time  required  for  the  water  to  drain  from  the  field. 
Generally  the  water  is  removed  when  most  of  the  heads  of  the 
rice  are  in  the  dough  stage,  the  end  grains  have  begun  to  harden 
and  the  heads  have  turned  yellow  and  filled  enough  so  that 
most  of  them  have  turned  down. 

Along  the  lower  part  of  the  Mississippi  River  and  the  Atlantic 
Coast  where  the  rice  is  still  cut  with  sickles,  the  water  is  left 
longer  on  the  field,  and  in  some  cases  is  drained  off  only  the 
day  before  the  rice  is  cut.  In  all  sections  the  bundles  of  rice 
are  shocked  on  the  field  and  threshed  by  threshing  machines 
driven  by  steam  or  gasoline  engines. 

MARKETING. — Rice  is  generally  sold  to  the  rice  mills  through 
buyers  who  go  over  the  country  during  threshing  time  to  sample 
the  rice.  Frequently  several  buyers  bid  on  the  same  rice. 
During  recent  years  the  rice  buyers  have  organized  a  sales 
company  called  the  Southern  Rice  Growers  Association,  the 
object  of  which  is  to  give  stability  to  the  rice  market  and  protect 
the  growers  by  regulating  the  price,  grading  the  rice,  and  selling 
it  for  the  highest  possible  price,  under  the  greatest  competition 
from  the  buyers.  The  rice  growers  sign  a  contract  agreeing 
not  to  sell  their  rice  for  less  than  the  price  fixed  for  that  grade 
of  rice  by  the  association.  In  consideration  of  the  assistance  of 
the  association  in  selling  the  rice  and  to  provide  a  fund  to  be 
used  to  increase  the  consumption  of  rice,  each  member  of  the 
association  pays  into  its  treasury  7  cents  a  sack  when  his  rice 
is  sold. 

COST  AND  PROFITS. — The  cost  of  growing  rice  varies  with  the 
character  of  the  soil,  the  price  of  labor,  the  cost  of  irrigation 
water,  etc.  For  the  prairie  lands  of  Louisiana  and  Texas,  when 
irrigation  water  is  secured  from  canals,  the  approximate  cost  of 
growing  rice  is  given  on  the  following  page. 

This  estimate  is  based  on  what  a  farmer  could  be  hired  to  do 
the  work  for  at  regular  prices.  Where  the  farmer  owns  the  equip- 
ment and  does  his  own  work  or  hires  a  hand  by  the  month,  the 
outlay  will  not  be  so  great,  since  this  estimate  allows  wages  for 
the  farmer  and  his  teams  and  tools.  According  to  the  December 


IRRIGATION  OF  STAPLE  CROPS  231 

Crop  Report  of  1912,  the  average  yield  of  rice  per  acre  from 
1009  to  1912,  for  Texas  and  Louisiana  was  34  bushels,  or  9.44  bar- 
rels, and  the  average  price  received  during  those  years  was 
S0.80  a  bushel,  or  $2.80  a  barrel.  This  makes  a  return  of  $27.20 
per  acre  or  $1.15  per  acre  less  than  the  estimated  complete  cost 
of  production.  Both  yield  and  price  vary  with  different  seasons. 

Plowing $1 . 50 

Double  disking 0.85 

Double  harrowing 0 . 60 

Seed  rice 3 . 00 

Fertilizing 1 . 00 

Planting 0 .65 

Rolling 0.30 

Repairing  field  levees 0 . 35 

Irrigation  water 7 . 00 

Handling  water  on  field 0 . 40 

Cutting  rice 1 . 25 

Binder  twine 0 .30 

Shocking 0 . 50 

Threshing 3 . 00 

Marketing 0.90 

Sacks  (at  10  cents  each) 1 . 00 

Handling  rice 0 . 50 

Warehouse  storage  and  insurance 0 . 75 

Interest  at  8  per  cent,  on  land,  houses,  barn,  etc.,  and 

loss  of  work  animals. . .  4 . 50 


Total $28.35 

COST  OF  PRODUCTION  ON  THE  ARKANSAS  PRAIRIES. — The  fol- 
lowing itemized  cost  per  acre  of  producing  rice  on  the  prairies  of 
Arkansas  where  irrigation  water  is  secured  from  wells,  is  based  on 
what  the  cost  would  be  if  hired  at  market  prices. 

This  estimate  is  based  on  the  regular  price  of  $6  per  day  for 
a  four-mule  team  and  machine  or  wagon  and  driver.  The 
difference  in  the  cost  of  production  in  Arkansas  and  that  of  the 
Gulf  Coast  is  largely  due  to  the  greater  cost  of  irrigation  water. 
According  to  the  Crop  Reporter,  December,  1912,  the  average 
yield  of  rice  for  Arkansas  from  1909  to  1912,  was  40.8  bushels, 
or  11  1/3  barrels  per  acre,  and  the  average  price  received  for  the 
same  years  was  $0.84  per  bushel  or  $3.02  per  barrel.  This 
makes  a  return  of  $34.26  per  acre  and  leaves  $2.91  per  acre  more 


232  USE  OF  WATER  IN  IRRIGATION 

than  the  cost  of  production.  The  causes  of  the  larger  yields  and 
better  prices  for  Arkansas  rice  are  that  a  larger  part  of  the  land 
is  new  and  the  crops  are  given  more  careful  attention  than  on 
the  Gulf  Coast.  The  yield  and  price  of  rice  in  Arkansas  have 
gradually  fallen  and  will  be  about  the  same  as  in  other  states  in 
a  few  years,  when  much  of  the  land  becomes  old. 

Plowing $1 . 50 

Double  disking 0 . 85 

Double  harrowing , 0 . 60 

Seed  rice 3 . 00 

Planting 0 . 60 

Repairing  levees 0 . 20 

Irrigation  water 10 . 00 

Handling  water  on  land 1 . 00 

Cutting  rice 1 . 50 

Binder  twine 0 . 40 

Shocking .  0 . 60 

Threshing 4.00 

Marketing 1.10 

Sacks  (at  10  cents  each) 1 . 20 

Hauling 0.80 

Warehouse  storage  and  insurance  interest  at  8  per 

cent,  on  land,  houses,  barn,  etc 4 .00 


Total $31.35 

40.  The  Growing  of  Cotton  under  Irrigation. — About  three- 
fourths  of  the  cotton  produced  in  the  world  is  grown  in  the 
United  States.  Cotton  is  also  grown  in  India,  Egypt,  Asiatic 
Russia  (Turkestan),  China,  Brazil,  Peru,  Mexico,  Turkey  and 
Persia.  Cotton  crops  are  artificially  watered  in  Egypt,  India, 
Algeria,  Persia,  Turkestan,  Mexico,  Peru  and  Brazil  but  the 
practice  in  this  country  is  of  recent  origin.  In  1908  there  were 
less  than  5000  acres  of  irrigated  cotton  in  the  United  States 
while  in  1913  the  acreage  had  increased  to  80,000  acres.  Cotton 
is  produced  in  all  of  the  southern  boundary  states  from  Georgia 
to  California  but  only  in  California,  Arizona,  New  Mexico  and 
southwest  Texas  is  it  necessary  to  apply  moisture  artificially 
to  produce  a  commercial  crop. 

In  outlining  the  best  practice  to  adopt  in  the  culture  and 
irrigation  of  cotton  in  this  country  the  writer  desires  to  acknowl- 
edge the  assistance  he  has  received  from  Mr.  W.L.  Rockwell,  C.  E., 


IRRIGATION  OF  STAPLE  CROPS  233 

of  San  Antonio,  Texas,  who  has  gained  through  close  observa- 
tion and  long  experience  an  intimate  knowledge  of  the  behavior 
of  this  plant  under  irrigation. 

PREPARATION  OF  THE  SOIL. — Cotton  is  a  semi-tropical  plant 
and  as  such  thrives  best  under  a  hot  sun  and  in  a  warm  soil. 
A  high  moisture  content  tends  to  reduce  soil  temperature,  hence 
cotton  makes  the  best  growth  in  a  moderately  moist  soil.  Pro- 
duced under  proper  conditions  the  cotton  plant  is  very  sym- 
metrical. It  sends  a  tap  root  deeply  into  the  subsoil,  and  this 
is  surrounded  by  a  uniformly  distributed  system  of  rootlets. 
The  plant  is  a  strong  feeder  and  requires  a  large  area  from  which 
to  draw  its  nourishment.  It  thrives  best  in  a  rather  firm  seed 
bed,  which  in  irrigation  is  readily  obtained.  It  is  good  practice 
to  plow  the  ground  as  early  and  as  deep  as  possible.  Fall  plow- 
ing is  to  be  preferred  to  spring  plowing.  If  at  planting  time 
the  soil  does  not  contain  sufficient  moisture  to  germinate  the 
seed  and  start  plant  growth,  water  should  be  applied  moistening 
the  ground  to  a  good  depth.  After  irrigation,  mulch  the  soil 
and  plant  immediately. 

VARIETY  AND  SEED. — The  cotton  plant  has  two  kinds  of  branches 
whose  functions  are  distinctive.  These  are  the  vegetative,  or 
those  forming  the  framework  of  the  plant,  which  are  produced 
upright  and  bear  no  fruit,  and  the  fruiting,  which  are  thrown 
out  laterally  from  the  vegetative  stems  and  carry  the  fruit. 
The  variety  grown  should  be  one  which  is  well  supplied  with 
fruit  stems  from  the  ground  upward  and  each  fruiting  branch 
should  retain  from  three  to  six  bolls  and  rapidly  develop  these 
to  maturity.  The  bolls  should  be  large,  of  good  length,  uni- 
formly cylindrical  and  the  percentage  of  lint  high.  The  fiber 
should  be  long,  strong  and  of  fine  texture.  A  variety  should  be 
selected  which  is  not  inclined  to  " throw  off"  squares  when 
water  is  applied,  or  when  the  temperature  is  high.  When  mature 
the  bolls  should  open  well,  but  in  such  a  manner  that  the  lint 
will  not  waste  badly  during  storms. 

To  secure  these  characteristics  and  habits  the  seed  should 
be  selected  from  marked  plants  in  the  field,  the  selections 
being  made  during  the  growing  and  maturing  periods.  Cotton 
is  a  plant  that  readily  hybridizes  and  deteriorates,  so  to  main- 
tain a  uniformly  high  grade  of  produce,  seed  selection  is  of  para- 


234  USE  OF  WATER  IN  IRRIGATION 

mount  importance.  To  produce  upland  and  long  staple  varieties 
on  adjoining  farms,  pure  seed  must  be  obtained  every  second 
or  third  year,  and  if  other  varieties  of  cotton  are  grown  near 
fields  of  Egyptian,  pure  seed  of  the  latter  type  must  be  imported 
each  year. 

The  upland  varieties  as  well  as  the  long  staple  may  be  pro- 
duced over  the  entire  irrigated  cotton  area,  though  varietal 
habits  and  characteristics  adapt  certain  types  to  certain  locali- 
ties. Egyptian,  being  a  long  season,  late  maturing  plant  can 
not  be  successfully  grown  in  districts  infested  with  the  boll 
weevil. 

TIME  OF  PLANTING. — The  young  cotton  plant  does  not  thrive 
during  cool  cloudy  days,  and  the  maturing  of  the  crop  is  not 
hastened  by  too  early  planting.  In  southwest  Texas  it  may 
be  planted  after  March  1  until  April  1;  in  west  Texas,  New 
Mexico,  Arizona  and  southern  California  from  March  15  to  April 
15.  The  short  staple,  short  season  cotton  may  be  planted  in 
districts  not  infested  with  the  boll  weevil  as  late  as  May  15. 

PLANTING. — The  customary  method  of  planting  in  the  Salt 
River  Valley,  Arizona,  is  to  throw  a  ridge  or  back  furrow  every 
4  feet  and  plant  the  seed  with  a  hoe  drill  provided  with  a 
covering  wheel  in  the  center  of  each  ridge.  This  method 
splits  the  original  ridge  into  two  smaller  ones  which  effectively 
prevent  the  irrigating  water  breaking  into  the  seed  row  and 
leaves  an  irrigating  furrow  on  each  side.  The  quantity  of  seed 
per  acre  varies  from  25  to  30  pounds. 

The  depth  of  planting  is  regulated  by  the  nature  of  the  soil 
and  percentage  of  moisture  present.  The  seed  should  not  be 
placed  as  deep  in  a  clay  as  in  a  sandy  loam.  From  1  to  2 
inches  are  allowable,  but  seldom  is  it  advisable  to  plant  over  1  1/2 
inches  in  depth. 

SPACING  AND  THINNING. — A  close  study  of  the  characteristics 
and  habits  of  the  cotton  plant  have  recently  brought  about 
changes  in  the  methods  of  culture,  particularly  in  the  width 
allowed  between  plants  in  the  row,  as  well  as  the  distance 
between  rows.  It  has  been  found  that  when  the  plants  are 
young,  to  allow  them  to  crowd  each  other  in  the  row  holds  in 
check  the  vegetative  growth.  This  treatment  also  prevents 
the  production  of  vegetative  branches  and  induces  the  develop- 


IRRIGATION  OF  STAPLE  CROPS  235 

merit  of  fruiting  branches.  The  proper  distances  between 
plants  in  the  row  can  not  be  definitely  stated  since  this  is  gov- 
erned by  variety,  type  of  soil,  and  other  conditions.  Investi- 
gations thus  far  conducted  indicate  that  a  gradual  thinning 
gives  better  results  than  if  all  extra  plants  are  removed  at  one 
time.  By  thinning  to  a  distance  of  3  or  4  inches  when  the 
plants  are  6  to  8  inches  high,  then  by  a  second  spacing  to  10  or 
12  inches,  in  sandy  soils,  15  inches,  when  the  plants  are  10  to  12 
inches  tall,  a  more  uniform  stand  is  secured,  and  the  crowding 
process  is  more  uniformly  maintained,  thus  securing  a  reduction 
in  the  vegetative  branches.  If  these  branches  are  allowed  to 
develop  wide  spacing  becomes  necessary,  else  the  rank  foliage 
will  shade  the  early  fruit,  prevent  its  maturing  and  only  a  light 
top  crop  will  be  secured.  The  width  between  rows  varies  from 
36  inches  to  54  inches  according  to  soils  and  variety,  lighter 
soils  requiring  the  greater  widths. 

METHODS  OF  IRRIGATING. — Cotton,  like  other  cultivated  crops, 
is  irrigated  by  means  of  head  ditches  and  furrows.  The  distance 
between  head  ditches  should  not  exceed  350  feet  in  sandy 
soils  and  450  feet  in  clay  loams.  Most  soils  in  warm  climates 
bake  after  being  thoroughly  wet.  On  this  account,  the  water 
should  not  be  permitted  to  overflow  the  soil  around  young 
plants.  In  this  regard  the  irrigation  of  cotton  resembles  that 
of  potatoes. 

PROPER  TIME  TO  IRRIGATE. — It  is  doubtful  whether  there  is 
another  annual  crop  produced  that  responds  so  favorably  to 
proper  methods  of  treatment.  In  the  rich  valley  soils  of  the  arid 
southwest  there  is  a  tendency  to  rank  weed  growth.  With 
crops  producing  fruit  like  cotton  this  must  be  prevented  or 
held  in  check.  The  soil  at  the  time  of  planting  should  be  moist 
for  at  least  4  feet  in  depth  under  which  condition  a  considerable 
time  may  elapse  before  it  will  be  necessary  to  apply  more. 
The  surface  soil  will  gradually  lose  a  part  of  its  moisture  and 
the  roots  will  be  induced  to  seek  moister  soil  at  lower  depths. 
A  large  feeding  area  is  thus  made  available  and  the  roots  are 
removed  from  the  unfavorable  climatic  influences  existing  near 
the  surface.  By  withholding  moisture  at  the  proper  degree 
and  following  the  method  of  close  planting  advocated  the  wood 
growth  is  held  in  check  and  the  plant  kept  in  a  healthy  normal 


236  USE  OF  WATER  IN  IRRIGATION 

state.  While  in  this  condition  it  is  best  fitted  to  throw  out 
fruiting  branches  and  to  begin  setting  fruit.  Before  a  large 
number  of  flowers  appear  the  crop  should  be  given  a  2  to  3-inch 
irrigation  and  during  the  period  of  fruit  setting  the  soil  should 
be  maintained  uniformly  moist — not  so  moist  as  to  produce  a 
glossy,  sappy  appearance  of  the  plant  leaves,  but  one  of  healthy, 
balanced  growth.  The  field  is  in  fine  condition  when  in  looking 
over  it  flowers  are  more  in  evidence  than  leaves.  The  soil  must 
not  be  allowed  at  this  stage  to  become  so  dry  as  to  check  the 
growth,  for  if  this  occurs,  when  water  is  applied  the  plants  will 
" throw  off"  their  squares.  Soil  and  other  conditions  are  so 
varied  that  no  rule  can  be  given  regarding  the  interval  between 
irrigations.  This  must  be  determined  by  the  farmer  in  studying 
the  soil  and  the  condition  of  the  crop  at  various  stages  of  growth. 
In  close  clay  soils  light  applications  at  short  intervals  seem  best, 
while  in  open  soils  heavier  waterings  at  longer  intervals  will 
bring  better  results. 

CULTIVATION. — Deep  plowing  before  planting  opens  the  soil 
to  the  air  and  the  first  irrigation  firms  the  seed  bed  which  is 
necessary  for  cotton.  Cultivation  should  begin  as  soon  as  the 
plants  appear  and  continue  until  they  become  too  large  to  cul- 
tivate between  the  rows.  The  cultivation  should  be  shallow  and 
the  sweep  and  harrow  are  the  best  tools  to  use.  A  very  fine 
tooth  adjustable  harrow,  in  two  sections  and  large  enough  to 
cultivate  two  spaces,  should  be  used  after  an  irrigation,  since 
with  this  tool  cultivation  can  be  begun  earlier  than  with  a 
sweep.  This  implement  also  breaks  up  the  surface  so  that  it 
can  be  more  readily  pulverized  by  the  sweep. 

COST  OF  PRODUCTION. — The  cost  of  production  and  returns 
from  a  one-bale  crop  of  upland  cotton  is  herewith  itemized. 
This  estimate  is  based  on  labor  at  $1  per  day  without  board, 
horses  $0.75  per  day  with  board,  irrigation  water  $4  per  acre  per 
season. 


IRRIGATION  OF  STAPLE  CROPS                237 

Plowing  ground $2.50 

Seed 1 . 00 

Irrigation,  water 4 . 00 

Irrigation,  labor 1 . 00 

Thinning 1 . 00 

Cultivation 5 . 00 

Picking,  1500  pounds  seed  cotton  @  75  cents  1 1 . 25 

Ginning  and  baling 3 . 50 

Marketing 1.00 


Total $30.25 

Overhead  expenses 

Six  per  cent.  int.  on  $150  land 9.00 

Taxes 1.00 

Interest  and  depreciation  on  tools 1 . 00 


$11.00 

Total  cost  of  production  not  allowing  for  superin- 
tendence      $41 .25 

Returns 

500  pounds  lint  cotton  at  10  cents $50 . 00 

1000  pounds  seed  at  $25  per  ton 12.50 


Total % 62.50 

Net  returns $21 . 25 

The  cost  of  production  of  the  long  staples,  such  as  Durango, 
Snowflake  and  Blackseed  would  be  about  $55,  the  difference  being 
in  the  picking  and  ginning.  It  is  worth  about  5  cents  more  per 
pound  than  the  Uplands  and  the  returns  would  be  about  as 
follows : 

500  pounds  lint  at  15  cents $75 . 00 

1000  pounds  seed  at  $25  per  ton 12 . 50 


Less  cost  of  production 55 . 00 

Net  returns $32.50 

Cost  and  returns  of  Egyptian  cotton  in  the  Salt  River  Valley, 
Arizona,  no  allowance  being  made  for  superintendence,  is  as 
follows: 


238  USE  OF  WATER  IN  IRRIGATION 

(One  bale  crop) 

Plowing  ground $3 . 50 

Seed 1.00 

Irrigation,  water 2 . 00 

Irrigation,  labor 1 . 00 

Thinning 1 . 00 

Cultivation 7 . 50 

Picking,  1780  pounds  seed  cotton  at  $2.  .  .  35.60 

Ginning  and  baling 12 . 00 

Marketing 1 . 00 


Total  cost $64.60 

Overhead  expense 

Interest  on  $150  land 9 . 00 

Taxes 1.00 

Interest  and  depreciation  on  tools 1 . 00 


11.00 
Total  cost $75 .60 

Returns 

500  pounds  lint  at  20  cents $100.00 

1200  pounds  seed  at  $25  per  ton 15 . 00 


$115.00 
Less  cost  of  production 75 . 60 


Net  returns $39 . 40 

Mr.  Rockwell  believes  that  an  average  yield  of  one  and  one- 
half  bales  per  acre  is  possible  throughout  the  irrigated  districts 
when  proper  care  and  skill  are  exercised  by  the  grower.  He 
considers  the  following  features  of  first  importance.  (1)  Early 
and  deep  plowing,  (2)  thorough  irrigation  before  planting  fol- 
lowed by  a  limited  moisture  supply  after  planting  until  the  first 
flowers  appear,  (3)  a  sufficient  and  uniform  moisture  supply 
during  the  fruiting  period,  (4)  a  continuous  shallow  cultivation, 
(5)  close  planting  in  the  row  and  subsequent  crowding  to  hold 
in  check  the  vegetative  branching,  (6)  thinning  gradually  10  to 
15  inches  apart  by  at  least  two  operations. 

41.  The  Growing  of  Sugar  Cane  under  Irrigation. — Sugar 
cane  is  produced  in  all  the  Gulf  States  from  Florida  westward 
and  for  a  distance  of  more  than  200  miles  inland  from  the  Gulf. 


IRRIGATION  OF  STAPLE  CROPS  239 

Though  grown  in  a  number  of  southern  states  it  is  only  in  Texas 
and  in  the  island  possessions  of  the  United  States  that  it  is  irri- 
gated. This  subtropical  plant  requires  a  long  growing  season 
of  at  least  10  months  to  produce  a  profitable  crop.  In  the  Hawai- 
ian Islands  the  first  crop  from  seed  requires  18  months  to  mature 
and  the  subsequent  or  stubble  crops  22  months  to  reach  maturity. 
The  average  crop  thus  obtained  yields  about  41/2  tons  of  sugar 
per  acre.  Coming  inland  from  the  Gulf  of  Mexico  in  Texas  a 
distance  of  75  miles  or  more  the  frostless  period  is  not  sufficient 
in  length  to  produce  a  commercial  crop  of  sugar  but  over  a  con- 
siderable area  cane  is  grown  for  the  manufacture  of  sirup. 

PREPARING  THE  SOIL. — Soils  for  sugar  cane,  according  to  Mr. 
Rockwell,  should  be  rich  in  vegetable  matter  to  furnish  nourish- 
ment to  the  plant  and  to  facilitate  drainage.  If  the  soil  is  de- 
ficient in  humus,  green  crops,  particularly  leguminous  crops  should 
be  plowed  under.  This  can  be  readily  done  by  a  proper  rotation. 
Soils  adapted  to  the  growth  of  sugar  cane  in  this  country  are 
close  grained  and  require  deep  plowing  and  subsoiling.  The  stir- 
ring of  the  soil  to  a  depth  of  20  inches  is  beneficial.  Fields  should 
be  plowed  as  long  as  possible  before  planting  and  the  surface 
thoroughly  mulched  with  a  disk. 

PLANTING. — Sugar  cane  is  reproduced  for  commercial  purposes 
by  planting  the  stocks.  Great  care  should  be  exercised  in  their 
selection  which  should  be  made  near  the  end  of  the  growing 
period.  Only  a  vigorous,  early  maturing  stock  should  be  chosen, 
having  a  good  length  of  joint  and  plump,  well-matured  buds. 
The  selected  stock  should  be  left  standing  as  long  as  possible 
without  injury  from  frost.  Planting  should  begin  whenever  the 
seed  crop  has  sufficiently  matured  for  vigorous  germination. 
The  planting  period  extends  from  October  into  the  winter  season 
but  early  planting  is  preferable  since  it  lessens  the  risk  of  damage 
by  frost  to  the  seed,  the  drying  out  of  the  buds  and  other  set- 
backs. 

The  rows  spaced  6  feet  apart  are  marked  by  a  single  shovel 
which  is  followed  by  a  large  middle  breaker  which  opens  the  fur- 
row 8  to  12  inches  deep  in  one  or  two  trips.  The  canes  are  cut 
in  lengths  of  4  to  5  feet  or  shorter  if  crooked  and  dropped  in  the 
furrow.  If  there  are  few  infertile  buds  one  stock  in  a  place  slightly 
lapped  at  the  joints  will  furnish  a  good  stand  but  if  there  is  a 


240  USE  OF  WATER  IN  IRRIGATION 

rather  high  percentage  of  poor,  weak  buds  it  may  be  necessary  to 
drop  two  stocks  alongside,  breaking  joints.  Thus  from  31/2 
to  51/2  tons  of  seed  per  acre  will  be  required.  When  the  seed 
is  covered  to  a  depth  of  3  inches  irrigation  water  is  run  down  the 
row  and  directly  over  the  cane.  The  field  is  then  harrowed  to 
create  a  soil  mulch  which  checks  evaporation  and  any  tendency 
to  soil  baking. 

IRRIGATION. — Sugar  cane,  not  unlike  other  cultivated  grasses, 
grows  most  luxuriantly  under  humid  conditions.  The  results  of  ex- 
perience seem  to  show  that  the  moisture  content  of  the  soil  should 
not  fall  below  25  per  cent,  during  the  season.  Dr.  W.  C.  Stubbs, 
at  one  time  Director  of  the  Louisiana  Experiment  Station,  states 
that  60  inches  of  well  distributed  rainfall  is  necessary  for  the 
largest  yields.  It  is  well  to  bear  in  mind,  however,  that  cane  pro- 
duced under  excessive  moisture  contains  a  low  percentage  of  sugar, 
the  heaviest  sugar  production  being  in  districts  of  light  rainfall 
where  the  moisture  is  largely  supplied  by  irrigation.  In  the  lower 
Rio  Grande  Valley  of  Texas  during  the  season  1908-09,  42  acres 
produced  44.75  tons  of  stripped  cane  per  acre.  The  soil  was  a 
sandy  loam  very  well  drained.  The  crop  was  planted  during 
November  and  December.  It  received  during  the  growing  season 
25  inches  per  acre  in  five  irrigations  and  8  acre-inches  which  were 
applied  before  planting  made  33  inches  in  all.  The  total  amount 
received  by  irrigation  and  rainfall  amounted  to  55.84  inches. 

In  retentive  soils  12  to  13  irrigations  of  4  inches  each  are  usu- 
ally applied  to  sugar  cane.  Two  of  these  are  generally  given  prior 
to  February  1.  In  the  5-month  period  from  February  1  to  July 
1  the  interval  between  irrigations  is  20  days  and  from  July  1 
to  September  30  it  is  30  days. 

While  a  high  moisture  content  in  the  soil  increases  the  yield 
it  also  increases  the  moisture  in  the  stock  which  adds  to  the  cost 
of  hauling  and  manufacture  and  undoubtedly  decreases  the  per- 
centage of  sucrose.  The  more  water  in  the  cane  the  more  the 
machinery  required  for  reducing  it  and  the  greater  the  time  con- 
sumed in  evaporating.  It  is  the  action  of  the  sun  on  the  leaves 
that  produces  the  sugar  in  the  plant  and  when  the  time  arrives 
for  maturing  and  producing  the  sugar  water  should  be  withheld. 

The  furrow  method  of  application  is  commonly  used  but  there 
is  a  difference  of  opinion  among  growers  as  to  the  proper  location 


IRRIGATION  OF  STAPLE  CROPS  241 

of  the  furrow.  Some  advocate  running  the  water  in  a  furrow 
along  the  cane  row,  others  in  two  shallow  furrows  on  either  side 
of  the  row  while  still  others  make  use  of  the  flat  central  furrow. 
All  growers  agree  in  running  the  water  along  the  row,  the  first 
two  applications  after  seeding.  The  difference  of  opinion  as  to 
the  location  of  the  furrows  arises  perhaps  from  the  action  of  the 
water  in  different  types  of  soil.  In  heavy  clay  soils  the  water 
reaches  the  roots  more  readily  if  applied  around  the  stocks  which 
it  follows  into  the  ground.  In  open  porous  soils  this  advantage 
is  lost  and  water  is  applied  more  readily  alongside  the  row.  The 
grower  should  watch  the  movement  of  moisture  and  learn  the  best 
method  to  apply  in  his  individual  case. 

Head  ditches  having  a  capacity  of  3  to  5  second-feet  are  con- 
structed across  the  field  at  intervals  of  300  to  600  feet.  The 
grades  of  these  ditches  may  vary  from  0  to  2  inches  per  100  feet. 
Ordinarily  heads  of  from  2  to  3  second-feet  are  used  in  irrigating, 
each  head  being  divided  between  5  to  10  furrows. 

CULTIVATION. — To  prevent  weed  growth  as  well  as  to  check 
evaporation  and  packing  of  the  soil,  cultivation  should  follow  the 
application  of  the  water  and  continue  until  the  cane  is  too  large 
for  such  treatment.  The  first  tool  used  after  irrigation  should  be 
one  that  will  pulverize  the  surface  without  turning  up  moist  soil 
from  below.  All  cultivation  should  be  shallow  as  cane  is  a  grass 
and  a  shallow-rooted  feeder.  Until  the  crop  thoroughly  shades 
the  ground  cultivation  should  be  continued. 

When  ready  for  harvesting  the  cane  is  stripped,  cut,  topped 
and  placed  in  windrows  on  the  ground  and  is  then  transported 
to  the  mill  on  wagons  or  treadways. 

COST  OF  PRODUCTION. — Assuming  that  raw  land  in  the  lower 
Rio  Grande  Valley,  Texas,  is  worth  $115  per  acre,  the  cost  of  clear- 
ing, leveling,  ditching  and  the  like  would  increase  its  value  to  $150 
per  acre.  Assuming  also  that  three  crops  are  harvested  before 
replanting,  only  one-third  of  the  total  cost  of  planting  should  be 
charged  to  each  annual  crop.  On  this  basis  the  various  items 
of  cost  per  acre  for  a  45-ton  yield  has  been  estimated  by  Mr. 
Rockwell  to  be  about  as  shown  on  page  242. 

If  one  figures  on  a  yield  of  25  tons  per  acre  which  sells  for  $3 
per  ton,  the  cost  would  be  reduced  to  about  $50  and  the  net  re- 
turns to  about  $37.50  per  acre. 

16 


242 


USE  OF  WATER  IN  IRRIGATION 


One-third  cost  of  planting $12 . 25 

Irrigation  water 6  . 00 

Labor  in  irrigating 3 . 00 

Cultivation  with  teams 5  . 50 

Hoeing  twice  over 2.25 

Cutting,  stripping  and  topping 7 . 00 

Hauling  1  mile 22 . 00 

Overhead  charges  for  interest,  taxes,  and  depreciation  12 . 00 

Total $70 . 00 

Gross  returns,  45  tons  at  $3 . 50 $157 . 50 

Net  returns $87 . 50 

Owing  to  the  heavy  yields,  long  seasons,  and  other  factors, 
large  quantities  of  water  are  used  in  the  irrigation  of  cane  in  the 
Hawaiian  Islands.  The  following  table  gives  a  summary  of  the 
results  obtained  at  the  Hawaiian  Experiment  Station. 

TABLE  No.  31 


Experiment 

Rainfall, 
inches 

Irrigation 
water  in 
acre-feet 

Total 
water, 
acre-feet 

Pounds  of 
sugar 
produced 
per  acre 

Various 

1897-1898 

46.5 

3.91 

7.78 

24,755 

crops 

1898-1899 

26.9 

6.33 

8.58 

29,059 

1899-1900 

Rattoon 

40.17 

5.92 

9.27 

26,581 

1899-1900 

Plant 

40.96 

7.21 

10.6 

30,682 

do 

Plat  21 

40.96 

8.84 

12.24 

47,580 

do 

Plat  22 

40.96 

8.00 

11.4 

45,268 

do 

Plat  23 

40.96 

13.5 

16.9 

54,605 

do 

Plat  24 

40.96 

8.08 

11.5 

42,505 

do 

Plat  25 

40.96 

20.2 

23.6 

44,387 

do 

Plat  26 

40.96 

8.33 

11.75 

31,890 

1903 

70.51 

5.08 

10.95 

24,164 

Lahaina.     One  inch  per 

week 

1905 

71.12 

4.92 

10.84 

20,956 

1903 

70.51 

9.84 

15.7 

23,939 

Two  inches 

per  week 

1905 

71.12 

10.5 

16.42 

28,698 

1903 

70.51 

14.58 

20.45 

26,497 

Three  inches  per  week 

1905 

71.12 

15.56 

21.5 

34,347 

1903 

70.51 

5.33 

11.2 

24,045 

Two  inches 

every  two  weeks 

1905 

71.12 

5.00 

10.92 

20,698 

1903 

70.51 

5.58 

11.45 

19,452 

Three  inches  every  two 

weeks 

1905 

71.12 

5.00 

10.92 

21,534 

IRRIGATION  OF  STAPLE  CROPS  243 

42.  Irrigation  of  Onions. — Onions  are  grown  chiefly  for  home 
consumption  in  all  irrigated  sections.  Conditions  in  the  South- 
west and  more  particularly  in  the  lower  Rio  Grande  Valley,  Texas, 
are  so  favorable  for  the  growth  of  onions  that  their  production  on  a 
commercial  scale  has  become  an  important  industry.  According 
to  W.  L.  Rockwell,  the  output  from  this  valley  in  1913  was 
2,000,000  crates  of  50  pounds  each  from  8000  acres. 

FALL  SEEDING  AND  SEED  BED. — Some  varieties  are  seeded  in  the 
spring  in  the  direct  and  ordinary  manner.  The  more  common 
practice,  however,  is  to  sow  the  seed  in  seed  beds  in  the  fall  and 
afterward  transplant  to  the  field.  The  white  Bermuda  is  the 
most  popular  variety  for  fall  seeding.  The  ground  chosen  for 
the  seed  bed  should  not  have  much  slope  and  should  be  thoroughly 
leveled  and  the  surface  pulverized.  Ordinarily  the  beds  are  laid 
out  10  to  12  feet  wide  and  30  to  50  feet  long  by  constructing  a  head 
ditch  along  the  ends  of  the  rows  and  throwing  up  a  back  furrow  at 
right  angles  to  the  head  ditch.  The  seed  is  drilled  in  by  hand 
late  in  September  or  early  in  October  on  a  flat  surface  not  to  ex- 
ceed 1/4  inch  in  depth  in  rows  12  inches  apart,  about  25  pounds 
of  seed  per  acre  being  used.  An  acre  of  seed  bed  will  furnish 
plants  for  8  acres  in  the  field.  The  soil  is  kept  moist  by  frequent 
light  flooding  or  sprinkling,  the  overhead  spray  method  being  well 
adapted  to  seed  bed  irrigation.  As  soon  as  the  plants  appear 
cultivation  with  hand  tools  begins.  By  December  1  to  15  the 
plants  should  be  the  size  of  lead  pencils  when  they  are  ready  to 
transplant. 

PREPARATION  OF  THE  FIELD. — The  field  should  be  well  plowed 
and  the  surface  thoroughly  leveled  and  pulverized.  Ordinarily 
the  furrow  or  border  method  of  irrigation  is  practised.  In  either 
case  the  head  ditches  are  spaced  from  35  to  200  feet  apart  and 
are  given  a  capacity  of  1  to  3  second-feet.  The  beds  are  made 
from  10  to  14  feet  wide  by  turning  a  back  furrow  with  a  turning 
plow  or  disk. 

TRANSPLANTING. — Care  should  be  exercised  in  securing  good  seed 
and  thrifty,  vigorous  transplants  are  of  equal  importance.  The 
latter  should  be  graded  to  secure  a  more  uniform  maturing  and  a 
better  crop.  They  are  pulled  from  a  moist  seed  bed,  the  roots 
clipped  to  1.4  inches  and  the  tops  cut  back,  leaving  a  plant  about 
5  inches  long.  They  are  distributed  along  the  row  set  3  or  4 


244  USE  OF  WATER  IN  IRRIGATION 

inches  apart  and  21/2  inches  deep,  the  soil  being  placed  closely 
about  them. 

IRRIGATION. — Immediately  following  transplanting  the  field  is 
irrigated  by  flooding  between  borders  or  along  the  rows.  One  to 
three  irrigations  may  be  necessary  prior  to  February  depending 
on  the  season.  During  the  growing  period  water  is  applied  every 
8  to  12  days  at  a  rate  of  1  1/2  to  4  inches  per  application.  Eight 
to  ten  irrigations  are  given  in  all,  totaling  12  to  30  inches.  Under 
economical  methods  of  distribution  and  use,  18  inches  will  mature 
a  crop.  Heads  of  from  1  to  3  second-feet  are  used,  a  second-foot 
being  divided  between  two  beds  or  else  between  20  to  35  rows. 

HARVESTING. — Upon  the  first  sign  of  the  tops  falling  irrigation 
should  cease.  When  the  plants  are  mature,  indicated  by  the 
fallen  tops,  they  are  plowed  out  with  a  single  shovel  plow,  placed 
in  windrows  and  allowed  to  dry.  The  roots  and  tops  are  then 
clipped  and  the  onions  placed  in  crates  and  hauled  to  the  sorting 
shed.  After  grading  they  are  packed  in  50-pound  crates  and 
stored  or  placed  upon  the  car. 

COST  OF  PRODUCTION. — Mr.  Rockwell  estimates  the  cost  of  pro- 
ducing a  crop  of  300  crates  per  acre  at  $139,  this  total  being  made 
up  of  the  following  items. 

Preparation  of  seed  bed $1 . 00 

Irrigation  of  seed  bed 0 . 50 

Seed 4.00 

Preparation  of  field 7 . 50 

Transplanting 12 . 00 

Irrigation  water 10 . 00 

Labor  in  irrigating 7 . 00 

Cultivation 6 . 00 

Plowing  and  windrows 3 . 00 

Topping  and  clipping 8 . 00 

Grading  and  crating 4 . 50 

300  crates  at  18  cents 54  . 00 

Hauling  to  car  3  miles 4 . 50 

Interest  on  land 12.00 

Taxes 2.00 

Depreciation  on  tools 3 . 00 


Total $139.00 

The  yields  vary  all  the  way  from  100  to  600  crates  per  acre  and 
the  price  from  50  cents  to  $1.50  per  crate. 


IRRIGATION  OF  STAPLE  CROPS  245 

43.  Irrigation  of  Grapes.  THE  NEED  OF  IRRIGATION. — The 
growing  of  grapes  under  irrigation  is  perhaps  less  usual  in  the 
western  United  States  than  their  growth  without  irrigation. 
This  is  mainly  due  to  the  fact  that  in  general  less  moisture  is 
required  for  grapes  than  for  most  other  fruits.  A  further  prob- 
able reason  is  that  the  advantage  to  be  gained  by  irrigating 
grapes  on  the  less  moist  soils  is  not  yet  fully  appreciated;  and 
besides,  considerable  areas  of  grapes  are  grown  on  hillsides  where 
water  for  irrigation  is  not  available  and  where  its  distribution 
would  be  very  difficult  even  if  it  were  at  hand. 

VARIETIES  USUALLY  GROWN. — While  grapes  are  found  through- 
out the  United  States,  their  commercial  production  in  the  west- 
ern United  States  is  mainly  limited  to  the  Pacific  States  and  they 
are  most  largely  found  in  California.  For  the  perfection  of  the 
grape  rather  higher  temperatures  are  required  during  ripening 
periods  than  obtain  in  the  mountain  areas  of  the  interior. 
While  the  commercial  grapes  of  the  eastern  and  central  states 
are  varieties  of  native  American  species,  the  commercial  grapes 
of  California  and  the  other  Pacific  slope  states  are  varieties  of 
the  European  species  Vinifera,  although  several  American  spe- 
cies, LS  Riparia,  and  Rupestris,  are  used  as  grafting  stock  for 
the  Vinifera  and  other  European  species  grown  commercially 
in  the  West.  Wickson  lists  the  following  as  the  most  popular 
varieties  among  California  fruit  growers:  Muscat,  Tokay,  Cor- 
nichon,  Thompson,  Emperor,  Malaga,  Rose  of  Peru,  Zinfandel, 
Black  Morocco,  Sweet  Water,  Verdal,  Carignane,  Black  Prince, 
Alicante,  and  Sultana. 

WHEN  AND  How  TO  IRRIGATE. — There  is  no  well-established 
practice  in  either  the  time  or  the  manner  of  irrigating  grapes.  In 
the  Fresno  section  of  California,  which  is  the  raisin-grape  center 
of  the  United  States,  where  the  ground  water  is  in  most  cases 
relatively  high,  it  is  customary  to  irrigate  only  during  the  first  2 
years  of  growth,  the  vines  receiving  ample  moisture  after  that 
from  below.  In  such  cases  the  usual  practice  is  to  apply  water 
twice  during  the  season,  with  a  total  seasonal  application  of  about 
1  acre-foot.  Some  growers,  however,  prefer  to  apply  the  same 
amount  in  four  irrigations  instead  of  two.  On  the  higher  ground 
about  Fresno  vineyardists  usually  apply  water  on  old  vineyards 
at  least  once  each  season.  In  the  vineyard  sections  of  Sacra- 


246  USE  OF  WATER  IN  IRRIGATION 

mento  and  San  Joaquin  Counties,  California,  some  growers  irri- 
gate more  frequently,  watering  every  7  to  14  days,  with  as  many 
as  14  or  15  in  a  season  not  being  uncommon.  Many  of  the  vine- 
yardists  in  these  counties,  however,  do  not  irrigate  at  all.  In 
the  Napa  and  Sonoma  county  grape  sections  of  California,  where 
the  annual  rainfall  averages  from  25  to  over  40  inches,  vineyards 
are  not  irrigated  nor  are  southern  California  vineyards  usually 
irrigated,  except  in  the  desert  sections,  as  about  Coachella  where 
they  receive  three  or  four  waterings  annually.  While,  as  indi- 
cated, practice  varies  widely,  the  general  principle  to  bear  in  mind 
is  that,  whether  they  receive  it  from  rainfall  or  by  irrigation,  vine- 
yards should  have  ample  moisture  prior  to  and  at  the  time  of 
budding  in  the  spring,  with  a  diminishing  amount  as  the  season 
advances.  The  quantity  to  apply  is  dependent  entirely  on  the 
retentiveness  of  the  soil  and  on  the  amount  lost  by  evaporation, 
from  15  to  20  acre-inches  per  year  probably  being  the  minimum 
quantity  it  is  desirable  to  apply  in  addition  to  rainfall.  Care 
must  be  taken  not  to  irrigate  late  enough  in  the  season  to  stimu- 
late growth  of  the  vines  beyond  ripening  of  the  fruit.  Bioletti 
holds  that  with  deep  soils  very  retentive  of  moisture  best  results 
are  obtained  by  withholding  all  irrigation  after  April,  the  moisture 
then  in  the  ground  to  be  conserved  by  cultivation.  In  shallower 
or  less  retentive  soils  he  holds  that  an  irrigation  just  after  the 
fruit  is  set  and  another  a  little  before  it  reaches  full  size  are  ad- 
visable. In  any  case,  too  frequent  irrigations  should  be  avoided 
with  grapes  as  with  other  deciduous  fruits. 

The  usual  method  of  irrigating  vineyards  is  by  means  of  furrows. 
About  Fresno,  California,  two  furrows  are  run  in  each  "land"  12 
to  24  inches  from  the  vines,  small  checks  being  placed  across  the 
furrows  every  four  or  five  rows  to  hold  the  water.  In  the  best 
practice  the  water  is  confined  to  the  furrows,  the  more  crude  prac- 
tice practically  resulting  in  the  basin  method  sometimes  used  in 
orchards.  Frank  Adams  states  that  "One  of  the  best  systems  of 
vineyard  irrigation  observed  in  California  was  seen  at  Elk  Grove, 
Sacramento  County.  There  furrows  about  12  inches  deep  are 
plowed  in  every  other  'land' by  means  of  a  five-horse  home-made 
sulky  lister  plow  with  enlarged  mouldboards,  the  furrows  later 
being  enlarged  to  a  bottom  width  of  about  6  inches  and  '  packed ' 
with  a  home-made  'logger'  constructed  like  an  ordinary  crowder 


IRRIGATION  OF  STAPLE  CROPS  247 

and  shod  with  steel  plates.  By  this  method  of  furrowing  shallow 
wetting  and  consequently  shallow  rooting  of  the  vines  are  pre- 
vented." 

44.  Irrigation  of  Small  Fruit. — The  berry  patch  is  almost  as 
common  and  almost  as  indispensable  on  irrigated  farms  as  the 
family  garden.  The  area  devoted  to  the  commercial  growing  of 
small  fruit  under  irrigation  is,  however,  comparatively  small  and 
is  of  necessity  limited  to  sections  having  easy  access  to  large 
markets. 

The  crops  discussed  in  this  article  include  strawberries,  rasp- 
berries, blackberries,  loganberries  and  dewberries.  The  methods 
of  cultivation  and  irrigation  of  these  crops  vary  only  slightly  in 
the  different  irrigated  sections. 

STRAWBERRIES. — Strawberries  are, the  most  important  berry 
crop  grown  commercially  in  the  West.  They  can  be  grown  on  a 
variety  of  soils  but  thrive  best  on  a  sandy  loam.  The  lighter 
soils  produce  earlier  berries  but  the  heavier  soils  often  give 
larger  yields  and  for  a  longer  period.  One  of  the  chief  essentials 
is  that  the  soil  be  well  drained  and  for  this  reason  a  porous  sub- 
soil is  desirable. 

Ground  which  is  intended  to  be  planted  to  strawberries  should 
be  plowed  8  to  10  inches  deep,  thoroughly  pulverized  and  brought 
to  a  uniform  grade  entirely  free,  if  possible,  from  high  spots  or 
depressions.  The  soil  should  contain  a  good  supply  of  moisture 
at  the  time  the  plants  are  set  out. 

In  setting  out  plants  a  good  way  is  to  make  a  hole  with  a 
trowel,  insert  the  plant  and  press  the  earth  firmly  around  it  with 
the  hands.  The  roots  should  be  cut  to  a  length  of  about  3  inches. 
It  is  a  good  plan  to  carry  the  plants  in  a  vessel  containing  water 
until  they  are  ready  to  set  in  the  ground.  There  are  two  general 
methods  of  planting,  known  as  the  hill  system  and  the  matted  row 
system.  The  former  system  consists  of  growing  the  plants  in 
rows  and  keeping  the  runners  cut  off.  In  the  matted  row  system 
the  rows  are  marked  off  3  to  4  feet  apart  and  the  plants  set 
1  to  2  feet  apart  in  the  row  and  the  runners  allowed  to  fill  the 
intervening  space.  There  are  various  modifications  of  these 
methods.  In  Oregon  if  plants  are  to  be  cultivated  both  ways  they 
are  usually  set  21/2X2  1/2  feet  apart  or  3  X  3  feet  apart. 
If  not  intended  to  be  cultivated  both  ways  they  are  set  4  1/2  X  3 


248  USE  OF  WATER  IN  IRRIGATION 

feet  apart.  In  southern  California  the  rows  are  usually  2  X  21/2 
feet  apart.  Sometimes  they  are  set  on  ridges  in  double  rows  6  to 
10  inches  apart,  the  ridges  being  30  to  32  inches  apart  between 
centers.  In  Colorado  if  the  hill  system  is  used  the  rows  are 
2  1/2  to  3  feet  apart  and  plants  12  inches  in  the  rows.  If  the 
matted  row  system  is  employed  the  plants  are  set  18  to  24  inches 
apart  and  the  rows  3  1/2  to  4  feet  apart.  By  the  hill  system  larger 
berries  are  produced  but  the  yield  is  larger  and  the  fruiting  period 
longer  when  the  matted  row  system  is  followed.  Size,  beauty  and 
good  shipping  qualities,  rather  than  flavor,  are  the  things  aimed 
at  by  the  commercial  grower.  Plants  may  be  set  out  either  in 
the  spring  or  fall  but  if  the  winters  are  at  all  severe  spring  plant- 
ing is  preferable. 

It  is  of  vital  importance  that  strawberries  have  an  ample 
supply  of  moisture  at  all  times,  especially  during  the  fruiting 
stage.  Few  plants  are  quicker  to  feel  the  effect  of  a  deficiency 
of  moisture  than  strawberries.  In  southern  California  water  is 
applied  every  6  to  10  days  throughout  the  growing  season. 
Local  soil  and  climatic  conditions  must  govern  the  amount  and 
frequency  of  irrigation  but  the  condition  of  the  soil  and  plants 
should  be  carefully  observed  and  water  should  be  applied  before 
the  plants  begin  to  suffer.  After  the  vines  cease  to  bear  one  or 
two  irrigations  usually  suffice. 

In  Colorado  the  best  practice  consists  in  making  shallow  fur- 
rows close  to  each  row  of  plants  as  soon  as  they  are  set  out  and 
water  is  applied  immediately  even  if  the  ground  is  moist.  This 
settles  the  earth  around  the  plants,  is  an  insurance  against  possi- 
ble dryness  and  gives  the  plants  a  vigorous  start.  In  order  to 
properly  regulate  the  amount  of  water  in  each  furrow  it  is  best 
to  take  the  water  from  the  supply  ditch  through  metal  tubes  or 
lath  boxes  rather  than  to  make  cuts  in  the  ditch  bank. 

Some  growers  prefer  to  irrigate  in  every  alternate  row  while  the 
dry  rows  are  being  picked.  This  makes  it  possible  for  irrigation 
and  picking  to  proceed  at  the  same  time.  It  is  important  that 
the  berries  be  picked  frequently,  every  day  if  possible,  as  it  is 
detrimental  to  the  vines  to  allow  fruit  to  decay  on  them. 

The  profitable  life  of  strawberry  vines  is  2  to  5  years. 
Most  growers  claim  they  are  not  profitable  after  the  third  year. 
Strawberries  should  be  cultivated  or  hoed  frequently  throughout 


IRRIGATION  OF  STAPLE  CROPS  249 

the  growing  season  in  order  to  keep  down  the  weeds  and  aerate 
the  soil.  One  large  grower  in  Pajaro  Valley,  Cal.,  cultivates 
ten  to  twelve  times  per  season  and  hoes  six  times. 

Among  the  popular  varieties  of  strawberries  grown  in  the  West 
may  be  mentioned  the  Brandywine  and  the  Klondike. 

IRRIGATION  OF  STRAWBERRIES  IN  SOUTHWESTERN  TEXAS. — 
The  cost  of  growing,  harvesting  and  the  profits  of  an  acre  of 
strawberries  are  given  in  the  following  table  compiled  by  C.  G. 
Haskell,  Austin,  Texas. 

Cost 

Plowing $2 . 00 

Ridging 1.50 

Fertilizing 4.00 

Plants 8.00 

Planting 4 . 00 

Cultivating  and  hoeing 15 . 00 

Mulching ' 20.00 

Irrigating 20 . 00 

Interest  on  investment ..                                 .  16.00 


$90.50 

Harvesting  102  crates  @  60  cents 61 . 20 

Crates  @  15  cents 15.30 

Selling  @  15  cents 15.30 


Total  cost $182 . 30 

102  crates  @  $2  per  crate $204.00 

Profit  per  acre $21 . 70 

Within  recent  years  truck  growers  in  southwest  Texas  have 
learned  the  value  of  supplemental  irrigation  for  their  crops,  espe- 
cially strawberries.  Conditions  are  favorable  for  pumping  water, 
the  lift  being  low,  from  30  to  40  feet,  the  supply  of  water  abun- 
dant and  fuel  oil  cheap. 

Water  is  pumped  to  the  highest  side  of  the  field  through 
2-  or  3-inch  iron  pipes.  It  is  taken  from  the  discharge  pipe  into 
light  galvanized  pipes,  movable  wooden  flumes  or  old  fire  hose 
from  which  it  is  distributed  to  the  rows.  The  rows  vary  in 
length  from  150  to  1000  feet,  about  400  feet  being  considered  the 
best  length.  The  water  is  usually  applied  in  every  alternate 
furrow  except  on  the  steep  slopes  where  it  is  applied  in  every  row. 
Only  enough  water  is  allowed  to  flow  in  the  furrows  to  reach  the 


250  USE  OF  WATER  IN  IRRIGATION 

lower  end  of  the  row,  care  being  taken  to  prevent  it  from  touching 
the  plants  or  wetting  the  tops  of  the  ridges.  The  best  practice 
is  to  irrigate  every  10  days  or  2  weeks  during  dry  weather,  the 
aim  being,  of  course,  to  apply  water  before  the  plants  begin  to 
suffer  for  lack  of  moisture. 

The  good  effects  of  irrigation  upon  the  yield  and  quality  of 
strawberries  in  this  section  is  very  marked.  Where  irrigated  and 
non-irrigated  strawberries  have  been  grown  side  by  side  it  has 
been  found  that  in  dry  years  the  yield  from  the  part  irrigated  was 
about  double  that  from  the  unirrigated  strawberries. 

RASPBERRIES. — Raspberries  are  of  two  general  kinds,  red  rasp- 
berries and  black  raspberries  or  black  caps.  Like  strawberries 
and  other  small  fruit  they  require  a  well-drained  soil.  In  the 
Pacific  Coast  States  they  are  planted  either  in  hills  6  to  8  feet 
apart  each  way  or  in  continuous  rows  5  to  8  feet  apart  and 
3  to  5  feet  apart  in  the  rows.  In  the  Rocky  Mountain  States 
if  winter  protection  is  necessary  the  rows  are  spaced  about  7  feet 
apart  and  plants  2  to  3  feet  apart  in  the  rows.  When  winter 
protection  is  not  necessary  the  rows  are  5  to  6  feet  apart  and 
the  plants  3  to  5  feet  apart  in  the  rows. 

In  sections  where  the  winter  temperature  is  likely  to  remain 
at  zero  or  lower  for  any  length  of  time  it  is  necessary  to  cover  the 
plants  to  protect  them  from  winterkilling.  This  is  accomplished 
by  removing  the  earth  from  one  side  of  the  row  and  bending  the 
canes  over  to  the  ground,  then  partially  covering  with  coarse 
manure  or  earth. 

In  California  the  planting  season  extends  from  November  to 
February  while  in  the  mountain  states  plants  may  be  set  out 
either  in  the  spring  or  fall,  spring  planting  being  preferred  if  the 
winters  are  severe. 

Raspberries  require  a  moderate  amount  of  water.  The  aim 
should  be  to  keep  the  surface  soil  in  a  fairly  moist  condition 
throughout  the  growing  season.  Water  is  applied  in  shallow 
furrows  as  near  to  the  rows  as  possible  without  danger  of  injury 
to  the  plants  in  cultivating.  Irrigations  should  occur  at  inter- 
vals of  10  days  to  3  weeks.  In  some  soils  even  more  frequent 
irrigation  may  be  necessary  but  frequent  cultivation  will  reduce 
the  number  of  irrigations  required.  Each  irrigation  should  be 
followed  by  a  shallow  cultivation.  Deep  cultivation  during  the 


IRRIGATION  OF  STAPLE  CROPS  251 

growing  season  is  never  advisable  for  bush  berries  of  any  kind, 
since  it  disturbs  the  delicate  feed  roots  near  the  surface.  Some 
growers  in  southern  California  have  an  extra  ridge  between  the 
rows  which  provides  a  dry  path  for  the  pickers  to  walk  on. 

It  is  a  good  practice  to  prune  all  old  canes  just  after  the  fruiting 
season  and  later  cut  the  main  canes  from  3  1/2  to  4  feet  in  length 
and  remove  all  small,  inferior  growth.  Where  there  is  danger  of 
winterkilling  it  is  best  not  to  remove  the  old  canes  until  spring. 

A  common  method  of  trellising  the  vines  is  to  sink  a  line  of 
posts  4  or  5  feet  high  in  the  row  to  which  an  18-inch  cross  arm  is 
nailed  3  feet  from  the  ground.  To  the  ends  of  these  arms  heavy 
wires  are  stapled  thus  forming  lateral  supports  for  the  canes. 
Many  growers,  however,  do  not  consider  it  necessary  to  provide 
supports  of  this  kind. 

The  Cuthbert  is  one  of  the  most  common  of  red  raspberries  and 
the  Gregg  is  prominent  among  the  black  caps. 

BLACKBERRIES. — What  has  been  said  regarding  raspberries 
applies  equally  as  w°ll  to  blackberries,  since  the  habits  and  re- 
quirements of  these  berries  are  very  similar.  The  blackberry  is 
hardier  than  most  other  bush  berries  and  will  not  suffer  as  quickly 
from  drought  but  an  ample  supply  of  moisture  is  nevertheless 
necessary  for  an  abundant  yield  of  large,  luscious  berries. 

DEWBERRIES. — These  berries,  distinguished  from  blackberries 
chiefly  by  their  low,  trailing  habit,  if  anything  are  probably  more 
dependent  on  water  than  are  blackberries.  They  are  planted 
shallower  than  blackberries  and  are  probably  best  irrigated  by 
means  of  furrows  midway  between  the  rows  rather  than  close  to 
them  as  is  the  case  with  blackberries.  Having  the  vines  high 
enough  to  keep  them  well  out  of  the  water  when  irrigating  has 
been  found  to  be  a  good  practice.  The  fruiting  season  of  the 
dewberry  is  earlier  than  that  of  the  blackberry  and  for  that 
reason  it  is  more  dependent  on  early  waterings. 

LOGANBERRY. — This  berry  is  a  California  hybrid  of  the  wild 
blackberry  and  red  raspberry.  Its  treatment  should  be  similar 
to  that  required  for  the  raspberry  except  that  it  is  less  adapted 
to  successful  growing  without  irrigation  and  is  usually  spaced 
wider  apart  in  the  rows. 

CURRANTS  AND  GOOSEBERRIES. — These  are  more  limited  in  their 
area  of  successful  growth  than  are  any  of  the  bush  fruits  previously 


252  USE  OF  WATER  IN  IRRIGATION 

mentioned,  due  chiefly  to  the  fruit  being  unable  to  stand  the  hot- 
ter sections.  In  California  they  are  usually  grown  commercially 
within  the  cooling  influences  of  the  coast.  They  should  be  irri- 
gated by  furrows  and  deeper  cultivation  is  possible  with  them 
after  irrigation  than  other  berries.  Ample  moisture  should 
always  be  kept  in  the  soil  during  the  growing  and  fruiting  seasons. 

45.  Supplemental  Irrigation  on  the  Atlantic  Coast. — Irrigation 
development  along  the  Atlantic  seaboard  differs  in  many  essential 
features  from  that  of  the  arid  region.  The  most  striking  of 
these  differences  pertain  to  the  size  of  tract  irrigated  and  the  form 
of  organization  adopted.  In  the  West  it  is  customary  to  include 
a  large  area  in  one  project  and  to  organize  farmers  under  it.  In 
the  East  a  small  area  comprising  the  most  fertile  parts  of  a  single 
farm  is  irrigated  by  the  owner.  This  may  be  accomplished  by 
one  of  three  systems  of  irrigation,  viz.,  surface,  subsurface  and 
overhead  spray,  or  by  combinations  of  the  first  and  third  as 
described  in  Art.  24.  The  plant  for  surface  irrigation  usually 
consists  of  a  gasoline  engine,  centrifugal  pump  and  underground 
mains  of  vitrified  clay  or  concrete.  The  equipments  for  the  other 
systems  named  have  been  described  in  Art.  23  and  24.  Potatoes, 
tobacco,  corn,  orchards,  bush  berries  and  other  row  crops  can  be 
successfully  irrigated  by  the  surface  method  providing  measures 
are  taken  to  adapt  it  to  local  conditions.  Owing  to  the  shallow 
soil,  the  surface  can  seldom  be  reduced  to  an  even  grade  by  re- 
moving earth  from  the  high  places  and  filling  up  the  low  places. 
Owing  also  to  the  undulating  character  of  the  surface  the  dis- 
tribution pipes  and  furrows  can  not  be  laid  out  with  that  regular- 
ity common  to  the  West.  As  a  rule  the  pipes  follow  the  ridges 
and  the  furrows  are  short.  At  intervals  of  about  40  feet  hydrants 
are  placed  on  the  pipes  and  to  these  are  attached  portable  surface 
pipes  from  which  the  water  is  distributed  over  the  surface  or  in 
furrows. 

Again  it  is  not  possible  to  figure  out  in  advance  the  amount  of 
water  that  will  be  needed  for  any  particular  crop.  If  the  season 
is  wet  little  water  may  be  required.  On  the  other  hand,  if  the 
season  is  dry  the  duty  of  water  may  approach  that  of  an  arid 
country.  There  is  likewise  much  uncertainty  in  applying  water. 
A  heavy  irrigation  may  be  followed  by  a  heavy  rainstorm. 

Taking  into  consideration  shallow-rooted  crops  in  shallow  soils 


IRRIGATION  OF  STAPLE  CROPS  253 

and  the  uncertainty  of  the  rainfall  it  is  better  to  apply  light 
irrigations  of  not  more  than  2  acre-inches  per  acre  whenever  the 
crops  are  in  need  of  water.  It  is  also  customary  in  planning  an 
irrigation  plant  to  allow  a  seasonal  duty  of  1  acre-foot  per  acre. 
This  is  reasonably  certain  to  suffice  for  all  crops  with  the  possible 
exception  of  alfalfa. 

The  investigations  conducted  by  Milo  B.  Williams  for  the  Office 
of  Experiment  Stations  have  demonstrated  that  the  economic 
advantages  of  irrigation  in  the  Atlantic  Coast  States  should  not 
be  measured  wholly  by  increased  yields  or  a  better  quality  of 
products.  Under  intensive  farming  where  large  sums  are  ex- 
pended for  fertilizers  waiting  on  rain  to  sow  the  seed  or  to  cultivate 
the  soil  may  prove  very  costly.  The  farmer  who  can  moisten 
the  soil  by  artificial  means,  and  plant  a  crop  gains  the  advantage 
of  having  highly  fertilized  soil  utilized  without  delay  from  dry 
weather.  The  time  thus  saved  often  makes  possible  the  growing 
of  an  additional  crop  on  the  same  ground  in  one  season  at  the 
same  cost  for  fertilizer  and  at  a  reduced  cost  for  labor.  By  prop- 
erly controlling  soil  moisture,  weeding  and  cutivating  can  be 
done  in  the  best  manner  at  the  least  expense  and  a  crop  of  maxi- 
mum yield  can  be  produced  in  the  shortest  time  and  with  the 
least  risk  from  disease,  frost,  or  other  unfavorable  conditions. 

One  of  the  greatest  advantages  of  supplemental  irrigation  lies 
in  the  fact  that  irrigated  crops  can  usually  be  marketed  ahead 
of  non-irrigated  crops.  Crops  can  not  well  be  planted  during 
droughts  and  if  planted  their  growth  is  checked.  By  applying 
water  when  needed  at  critical  stages  of  growth  the  irrigator  loses 
no  time  and  produces  a  heavy  crop  of  good  quality  which  he 
markets  before  the  bulk  of  like  crops  in  his  district  are  mature. 

46.  Dry -farming  in  its  Relation  to  Supplemental  Irrigation.— 
Dry-farming  is  the  growing  of  unirrigated  crops  by  special 
methods  of  tillage  and  cropping  in  regions  where  the  average  sea- 
sonal rainfall  is  not  sufficient  for  profitable  farming  if  ordinary 
methods  are  employed.  In  such  regions  it  is  necessary,  in  the  case 
of  row  crops  to  maintain  a  surface  mulch  by  frequent  cultivation 
which  will  prevent  to  a  large  degree  the  escape  of  moisture  by 
surface  evaporation,  and  in  the  case  of  small  grain,  hay,  or  forage 
crops  it  is  found  that  thin  seeding  is  advisable  since  a  few  strong 
plants  will  produce  a  larger  yield  of  a  marketable  product  than  a 


254  USE  OF  WATER  IN  IRRIGATION 

thick  stand  which  is  starved  for  lack  of  moisture.  Another 
common  practice  in  dry-farming  regions  is  known  as  sunnier  fal- 
lowing, which  consists  of  allowing  the  land  to  lie  idle  every  other 
year  and  by  keeping  it  free  from  weeds  and  maintaining  a  surface 
mulch,  store  water  in  the  soil  for  the  crop  planted  the  following 
year.  The  employment  of  special  methods  to  pack  or  firm  the 
soil  after  plowing,  the  growing  of  drought-resistant  crops,  and  a 
rotation  of  crops  which  includes  a  leguminous  crop  to  maintain 
the  fertility  of  the  soil  and  increase  its  water-holding  capacity,  are 
other  important  aids  to  successful  dry-farming. 

The  extent  of  land  which  is  adapted  to  dry-farming  is  not  very 
definitely  known.  Between  the  line  of  20-inch  rainfall  and  the 
margin  of  the  arable  lands  along  the  main  range  of  the  Rocky 
Mountains,  there  is  an  area  of  over  250,000,000  acres,  the  greater 
part  of  which  will  have  to  be  farmed,  if  at  all,  by  dry-farming 
methods.  In  addition  to  this  Great  Plains  area,  there  are  large 
areas  of  dry-farming  lands  on  the  Pacific  slope  of  the  Rockies. 
California,  for  example,  contains  over  10,000,000  acres  of  arable 
land  which  can  not  be  irrigated  on  account  of  the  lack  of  available 
water.  If  one  assumes  that  the  water  supply  of  the  seventeen 
western  states  will  be  wholly  utilized  when  50,000,000  acres  are 
irrigated,  there  will  remain  over  300,000,000  acres  of  arable  land 
to  be  dry-farmed  or  else  pastured. 

According  to  the  last  census,  sufficient  water  is  annually  diver- 
ted to  cover  the  entire  irrigated  area  of  this  country  to  a  depth  of 
over  57  inches.  To  furnish  and  apply  water  so  wastefully  to  even 
a  small  part  of  the  dry-farming  land  is  impracticable.  It  is,  how- 
ever, practicable  in  the  majority  of  cases  to  secure  from  1  to  1  1/2 
acre-feet  of  water  per  acre  for  small  tracts  that  are  intensely 
farmed  or  else  from  4  to  8~ acre-inches  per  acre  for  larger  tracts. 
This  is  what  is  meant  by  supplemental  irrigation  for  the  dry-farms. 
Water  supplies  for  this  purpose  can  be  obtained  from  streams  and 
wells.  As  a  rule  the  summer  flow  of  the  streams  is  diverted  and 
used  but  immense  quantities  of  water  go  to  waste  outside  of  the 
regular  crop-growing  season.  A  part  of  the  water  which  is  now 
wasted  might  be  stored  in  reservoirs  and  used  on  dry-farmed  lands. 
Another  part  might  be  diverted  in  the  late  fall,  winter,  or  early 
spring  and  stored  in  the  soil.  Then,  too,  underlying  a  part  of  the 


IRRIGATION  OF  STAPLE  CROPS  255 

vast  areas  of  dry-farming  lands  are  to  be  found  water-bearing 
strata  from  which  water  may  be  pumped. 

On  account  of  the  larger  returns  per  acre  from  a  small  tract 
which  is  both  irrigated  and  intensively  farmed,  a  farmer  is  justi- 
fied in  paying  much  more  than  the  average  price  for  water.  A 
small  storage  reservoir  when  safely  built  does  not  depreciate  in 
value  to  any  extent  and  costs  little  to  maintain.  The  main  item 
of  expense  is  the  interest  on  the  first  cost,  which  varies  from  a  few 
dollars  per  acre-foot  of  water  stored  to  over  $100. 

The  factory  cost  of  a  serviceable  14-foot  windmill  varies  from 
$150  to  $200. l  This  includes  the  steel  tower  40  feet  high  and  the 
pump.  The  freight  charges,  assembling  and  erecting  would  add 
$45  to  the  factory  price.  Much  of  the  work  of  digging  a  well  and 
of  building  a  small  reservoir  can  be  done  by  the  farmer  so  that  the 
total  outlay  of  cash  for  a  plant  of  this  kind  need  not  exceed  $450. 
The  maintenance  and  repair  bill  together  with  the  depreciation 
are  usually  high,  especially  when  the  windmill  is  not  properly 
cared  for. 

In  recent  years  oil-burning  engines  have  been  much  improved 
in  both  efficiency  and  serviceability.  Portable  engines  as  now 
manufactured  form  a  valuable  part  of  dry-farm  equipment.  The 
farmer  who  desires  to  pump  water  for  a  small  part  of  a  large 
dry-farm  can  now  make  his  selection  from  a  large  number  of  types 
of  internal  combustion  engines.  Apart  from  the  gasoline  engine 
proper,  there  are  on  the  market  engines  adapted  to  the  burning 
of  distillate,  crude  oil  and  semi-crude  oil.  Assuming  that  the 
land  is  carefully  prepared  for  irrigation  and  the  water  economic- 
ally applied,  a  duty  of  15  inches  in  addition  to  the  rainfall  will 
suffice  for  average  crops  in  dry-farming  districts.  The  cost  of 
raising  this  quantity  of  water  for  1  acre  from  a  well  100  feet 
deep  by  means  of  an  oil-burning  engine  and  a  good  pump  will 
vary  between  rather  wide  limits  depending  largely  on  the  price  of 
suitable  oils.  If  one  installs  a  gasoline  engine  and  burns  gasoline 
at  20  cents  a  gallon,  the  cost  per  acre  including  all  charges  will  not 
be  far  from  $11  for  the  season.  With  distillate  at  8  cents  a  gallon 
and  a  distillate-burning  engine  this  cost  may  be  reduced  nearly 
one-half.  Furthermore,  if  crude  oil  or  semi-crude  oil  can  be  ob- 
tained at  4  cents  a  gallon  and  used  in  a  crude-oil  or  Diesel  type  of 

1  The  use  of  small  water  supplies  for  irrigation.     Yearbook,  1908. 


256  USE  OF  WATER  IN  IRRIGATION 

engine  the  cost  may  be  still  further  reduced  to  about  $3.50  per 

acre.     In  using  an  electric  motor  and  current  at  2  1/2  cents  per 

K.  W.  the  cost  for  the  season  will  be  approximately  $6  per  acre. 

In  Bui.  70  of  the  Arizona  Experiment  Station  it  is  stated: 

"When  yields  of  35  to  50  bushels  of  milo  maize  per  acre  can  be 
obtained  by  pumping  from  4  to  6  acre-inches  of  water  upon  the 
land  during  the  winter  months  when  other  work  is  slack,  it  is 
useless  to  resort  to  the  great  amount  of  labor  required  by  summer- 
fallowing  to  produce  the  very  meager  yields  obtained  by  that 
method  of  farming.  The  increased  yields  by  supplemental  irrigation 
are  not  so  much  the  result  of  more  water  in  the  soil  as  of  a  small 
amount  of  water  applied  at  a  critical  time.  Thus  the  application  of 
2  to  3  inches  of  water  at  a  critical  time  makes  the  difference  between 
absolute  failure  and  satisfactory  success." 

At  the  Cheyenne  Experiment  Farm  in  charge  of  John  H.  Gordon 
oats  on  which  9.55  inches  of  water  were  applied  in  1913  yielded  63 
bushels  against  31  bushels  on  dry-farmed  land.  Wheat  which 
received  10.25  inches  yielded  35  bushels  against  13  bushels  on 
non-irrigated  land.  Alfalfa  which  received  only  13.20  inches  of 
irrigation  water  yielded  8500  pounds,  whereas  unirrigated  alfalfa 
produced  only  1800  pounds.  These  are  striking  examples  of  the 
beneficial  effects  of  a  small  amount  of  water  applied  at  critical 
periods  of  the  crop  growth. 

In  J.  A.  Widtsoe's  "  Dry-farming "  it  is  stated  that  Forbes  of 
Arizona  found  that  a  12-foot  windmill  pumping  water  from  a 
well  90  feet  deep  into  a  5000-gallon  storage  reservoir  supplied 
water  for  household  use  and  for  the  irrigation  of  61  olive  trees, 
2  cottonwoods,  8  pepper  trees,  1  date  palm,  19  pomegranates, 
4  grape  vines,  1  fig  tree,  9  eucalyptus  trees,  1  ash  and  13  miscel- 
laneous, making  a  total  of  87  useful  trees  and  32  vines  and  bushes. 

Widtsoe  also  states: 

"The  dry-farmer  should  carefully  avoid  the  temptation  to  decry 
irrigation  practices.  Irrigation  and  dry-farming  of  necessity  must  go 
hand  in  hand  in  the  development  of  the  great  arid  regions  of  the  world. 
Neither  can  well  stand  alone  in  the  building  of  great  commonwealths  on 
the  deserts  of  the  earth." 

It  is  evident  from  the  foregoing  that  a  wise  use  of  limited  water 
supplies  is  certain  to  become  an  important  factor  in  the  settle- 


IRRIGATION  OF  STAPLE  CROPS  257 

ment  of  semi-arid  lands  and  the  ultimate  success  of  dry-farming. 
Homes  cannot  be  established  without  water.  A  domestic  supply 
for  man  and  beast  is  indispensable.  Now  it  is  feasible  in  the 
majority  of  cases  to  increase  the  supply  for  household  and  stock 
purposes  sufficiently  to  irrigate  a  few  acres  around  the  home.  A 
small  amount  of  water  carefully  used  soon  brings  about  a  wonder- 
ful change.  A  green  lawn  covers  the  drifting  sand,  shade  trees 
intercept  the  burning  rays  of  a  western  sun,  cacti  and  sage  give 
place  to  flowers  and  fruit  and  vegetables  fresh  from  the  garden 
render  canned  goods  from  the  factory  no  longer  a  necessity.  In 
a  larger  sense  the  use  of  limited  water  supplies  on  the  dry  farm 
insures  a  much  larger  yield  by  applying  a  small  quantity  of  water 
to  the  crop  at  a  time  when  it  is  most  needed.  This  larger  yield 
means  closer  settlement,  better  social  conditions,  and  everything 
that  goes  to  make  up  our  best  rural  communities. 


17 


INDEX 


Acre-foot  per  foot,  definition  of,  63 
Acreage  irrigated  in  United  States,  2 
Adams,  Frank,  158,  187 
Adjudication  of  water  rights,  17 
Agencies  in  irrigation  development,  2 
Alfalfa  and  other  forage  crops,  174 
amount  of  water  required  for, 

182 

as  a  base  of  rotation,  176 
irrigation  of,  by  borders,  179 
by  checks,  181 
by  flooding,  178 
by  furrows,  181 
by  surface  pipes,  182 
influence  of  in  root  develop- 
ment, 177       % 
lands  adapted  to,  174 
preparatory  crops  for,  175 
seeding,  176 
winterkilling  of,  184 
Alkali,  black  and  white,  160 
plant  tolerance  of,  160 
plants  resistant  to,  161 
lands,  drainage  of,  167 
Appropriation  of  water,  15 
Arizona,  2,  3,  4 


Bark,  Don  H.,  82,  145,  193 
Basin  method  of  irrigation,  93 

flooding,  94 

ridger  used  in,  94 

sketch  of,  95 

Beckett,  S.  H.,  151,  152,  187 
Bixby,  F.  L.,  30 
Blackberries,  251 
Briggs,  L.  J.,  23,  149 
Brown,  Chas.  F.,  167 


California,  2,  3,  4 
Capillarity,  21,  25,  26,  112,  166 
Carey  Act,  2,  3,  10,  12 
Carpenter,  L.  G.,  144 
Check  method  of  irrigation,  91 
contour,  type  of,  93 
fields  irrigated  by,  92 
rectangular,  type  of,  93 
Cistern,  concrete,  44 
Colorado,  2,  3,  4 
Cone,  V.  M.,  58,  162 
Corrugation  method  of  irrigation,  80 
checks  for,  82 
corrugations  for,  81 
furrower  for,  81 
head  ditches  for,  80 

ditch  distributaries  for,  82 
of  water  for,  83 
Cost  of,  check  method  of  irrigation, 

93 

clearing  land,  65-68 
concrete  pipe,  47 
drainage,  172 
growing  cotton,  236 
onions,  244 
potatoes,  202 
raspberries,  250 
rice,  230 
sugar  beets,  209 

cane,  241 
irrigation,  3-6 
pipe  systems,  57 
rivetted  pipe,  53 
well  casing,  59 
Cotton,  232 

cost  of  producing,  236 
cultivation  of,  236 
extent  of  production  of,  232 
methods  of  irrigating,  235 


259 


260 


INDEX 


Cotton,  planting,  234 

preparing  soil  for,  233 

seeding,  233 

spacing  and  thinning,  234 

Crops,  profitable,  8 

revenue  from,  2,  10 
water  requirement  of,  146 

Crowder,  homemade,  73 

Culverts,  corrugated  pipe  for,  43 

Currants,  251 

Current  meter,  123 


D 


Delivery  of  water,  150 

forms  and  record  of,  157 
force  required  for,  158 
head  used  in,  159 
plan  of,  155 

regulations  governing,  153 
relations  of  irrigators  to  super- 
intendents in,  153 
Desert  Land  Act,  10 

entry,  12 
Dewberries,  251 
Diesem,  H.  C.,  30 
Ditches,    number    and    length    of, 

111 

farm,  33-39 

Drainage  of  irrigated  lands,  8,  166 
cost  of,  172 
drains  for,  168 
backfilling  of,  172 
depth  of,  168 
grade  of,  170 
kind  of,  168 
location  of,  168 
manholes  for,  172 
methods  of  installation  of,  171 
relief  wells  for,  169 
required  capacity  of,  170 
size  of  title  for,  170 
need  for,  167 

Dry  farming  in  relation  to  supple- 
mental irrigation,  253 
extent  of,  in  semi-arid  belt,  254 


Duty  of  water,  134 

British  Columbia  contract  gov- 
erning, 138 

conditions  affecting,  141 
court  decisions  governing,  137 
investigating,  144 
limitations  as  to,  17 
place  of  measurement  of,  140 
results  of  investigations  of,  146 
State  control  governing,  136 

laws  governing,  135 
units  of  measurement  for,  140 
water  right   contracts  govern- 
ing, 139 


E 


Educational  advantages,  9 
Efficiency  of  irrigation  water,  110 
Enterprises,  individual,  cooperative, 

etc.,  3,  10 

Equipment  for  new  settler,  28 
Ervin,  Guy,  200 

Evaporation  from  irrigated  soils,  128 
amount  evaporated,  130 
equipment    for    determining, 

130 
from  soil  and  water  compared, 

131 

from  water  surfaces,  125 
appliances  used  in,  125 
factors  governing,  127 
determination  of,  126 
records  of,  128 
Evaporation  losses,  131 

partial  prevention  of,  131 
Ewing,  P.  A.,  2 

Extent  of  irrigation    in    United 
States,  1 


Farm,  the  irrigated,  buildings,  32 
ditches,  32 

capacity  of,  35 
construction  of,  38 


INDEX 


261 


Farm  ditches,  flow  of  water  in,  35 
form  of,  34 
grade  of,  33 

instruments  for  laying  out,  37 
location  of,  33 
maintenance  of,  39 

irrigation  structures  for,  39 

lands,  extent  of  improved,  110 

laying  out,  30 

location  and  selection  of,  7 
Fippin,  E.  O.,  20,  21,  22,  27 
Fisher,  R.  W.,  212 
Flooding  methods,  83 
Forbes,  R.  H.,  164,  165,  256 
Foreman,  J.  H.,  212 
Fresno  scraper,  70 
Frosts,  occurrence  of,  7,  9 
Fruit,  small,  247 
Fuel  oil  "tops,"  62 
Fuller,  P.  E.,  139 
Furrow  method  of  irrigation,  73 

earthen  head  ditches  for,  73 

head  flumes  for,  73 
Furrower  for  corrugations,  81 
Furrows,  76 

distribution  of  water  in,  77 

length  and  location  of,  78 


Grain,  smut  in,  189 

when  to  irrigate,  190 

Grapes,  245 

irrigation  of,  245 
varieties  of,  245 

Grease  wood,  removal  of,  66 

Grunsky,  H.  W.,  137 

Gulf  States,  2 


Hanna,  F.  W.,  158,  159 
Harden,  F.  G.,  13 
Harding,  S.  T.,  39 
Hardpan,  18 
Hart,  R.  A.,  168 
Haskell,  C.  G.,  60,  220 
Head  ditches,  73,  80,  88,  90 

distributors  for,  82 

flumes,  wooden,  74 

concrete,  types  of,  74,  75 
Headgates,  wooden,  40,  41 

metal,  41 

concrete,  42 

Hilgard,  E.  W.,  19,  160,  161,  165 
Homestead  entry,  12 

law,  10 
Humid  region,  2 


Gardiner,  H.  C.,  31,  167 

Gates,  delivery,  40,  41 

used  in  Imperial  Valley,  Cal.,  42 
for  border  method,  88,  89 

Gieseker,  L.  M.,  151 

Gooseberries,  251 

Gordon,  John  H.,  256 

Grading  surface  of  fields,  69 

Grain,  186 

harvesting,    marketing,    profits 

of,  195 

irrigating  before  seeding,  189 
methods  of  applying  water  to, 

193 

preparation  of  soil  for,  187 
seasonal  rotation  of,  187 


Idaho,  2,  3,  4 

State  Land  Board  of,  146 
Indian  Service,  3 
Irrigation  districts,  3,  10,  12 

extent  of  in  United  States,  1 
Irrigator's  Supply  Co.  of  Ontario, 

Cal.  85 
Israelsen,  O.  W.,  22,  165 


Jayne,  S.  O.,  51,  68 
K 

Kansas,  2,  3,  4 
Kellar-Thomason  Mfg.  Co.,  42 


262 


INDEX 


Land  Office  circulars,  11 
Lands,  open  to  settlement,  9 

tabulated  information  concern- 
ing, 12 

price  of,  10 
Le  Conte,  J.  N.,  63 
Level,  homemade,  35 
Leveler,  rectangular  or  box,  71 
Loganberries,  251 
Loughridge,  R.  H.,  77,  211 
Lyon,  Thos.  L.,  20,  21,  22,  27 


M 


McCulloch,  S.  W.,  217 
McLaughlin,  W.  W.,  20,  186,  195 
Mead,  Elwood,  15 
Means,  Thos.  H.,  164 
Measurement  of  water,  115-125 

Australian  meter,  125 

current  meter,  123 

miner's  inch,  119 

proportional  division,  121 

slope  formulae,  125 

submerged  orifice,  120 

time-flow  method,  122 

unit  equivalents,  116 

units  used  in,  115 

Venturi  irrigation  meter,  122 

volumetric,  116 
Mesquite,  removal  of,  66 
Methods  of  irrigation,  72-107 
Mineral  salts,  injurious,  160 
Moisture  in  soils,  capillary  rise  of, 

26,27 
Montana,  2,  3,  4 


N 


Native  vegetation,  removal  of,  64 
Nebraska,  2,  3,  4 
Nevada,  2,  3,  4 
New  Mexico,  2,  3,  4 
North  Dakota,  2,  3,  4 


O 


O'Donnell,  I.  D.,  176 
Oklahoma,  2,  3,  4 
Onions,  243 

cost  of  producing,  244 

fall  seeding  of,  243 

harvesting,  244 

irrigating,  244 

preparation  of  field  for,  243 

seed  bed  for,  243 

transplanting,  243 
Orchards,  209 

grading  the  surface,  211 

intercropping,  216 

irrigation  of,  211 

amount  of  water  required,  214 
methods  of  application,  212 
number  of,  213 
time  of,  211 

selecting  land  for,  209 

winter  irrigation  of,  219 
Oregon,  2,  3,  4 


Peterson,  F.  L.,  151 
Pipe  cement,  for  subirrigation,  99 
concrete,  47 

Australian  method  of  making, 
49 

cost  of,  47 

Jagger  system  of  making,  48 

moulding,  48 
metal,  52 
rivetted,  52 

cost  of,  53 
systems,  53 

cost  of,  57 

fittings  for,  56 

hydrants  or  stands  for,  57 

Leeds,  Granville  W.,  55 
vitrified  clay,  49 

fittings  for,  49 

grades  of,  49 

prices  of,  50 


INDEX 


263 


Pipe   wood,  50 

how  made,  50,  51 

joints  for,  51 

prices  of,  52 
Pipes  and  stands,  75 
Planer,  homemade  levee,  87 
Plow,  wing,  38 
Potatoes,  195 

cost  of  growing,  202 

cultivation  of,  197 

effect  of  climate  on,  195 

effect  of  soil,  196 

harvesting,  201 

irrigation  of,  198 

marketing,  202 

planting,  196 

preparation  of  soil  for,  196 

rotation  of,  196 

sorting,  201 

spraying,  197 

yields  and  profits  of,  2GJ 
Preparation  of  surface  for  irrigation, 

68 
Pumps,  61 

Deane  Pump  Works,  62 

engines  and  motors  for,  62 

Layne  and  Bowler,  61 

Pomona  Mfg.  Co.,  62 


R 


Raspberries,  250 

Reclamation  Service,  U.  S.,  2,  3,  12 

Reservoirs,  46 

Rhead,  J.  L.,  42 

Rice,  acreage  devoted  to,  220 

amount  of  water  required  for, 

229 
cost  and  profits  of,  230 

of   production    in    Arkansas, 

231 
irrigation,  222 

Atlantic  Coast,  226,  228 
field  levees  for,  223 
methods    of    applying    water 
in,  226 


Rice,  irrigation,  securing  water  along 

Mississippi  for,  224 
structures  to  control  flow  in, 

224 

wells  for,  222 
marketing,  230 
planting,  221 

preparation  of  land  for,  221 
soil  and  climate  adapted  to,  221 
straight  head  or  blight  in,  228 
water  supply  for,  222 

weevil  in,  227 

Ridger  used  in  basin  method,  94 
Riparian  rights  to  water,  14,  18 
Robertson,  Ralph  D.,  89 
Rockwell,  W.  L.,  238,  243 
Root  crops,  irrigation  of,  195 


Sagebrush  grubber,  65 
removal  of,  64 

Saline  waters,  use  of,  162 

Schlicter,  Chas.  J.,  25 

Scobey,  F.  C.,  11,  40 

Scraper,  buck,  69 
Fresno,  70 

Seepage  losses,  111 

factors  influencing,  111 
in  percentage  of  flow,  112 
prevention  of,  112 
water,  rate  of  flow  of,  25 

Settler,  equipment  for,  28 

available  funds  necessary  for,  30 

Shantz,  H.  L.,  23,  149 

Slossen,  E.  E.,  164 

Social  advantages,  9 

Soil  moisture,  9,  21 

capillary,  21,  22,  25 
determining  content  of,  22 
forms  and  relationship  of,  22 
gravitational,  21 
hygroscopic,  21,  22 
movement  of,  24 
proper  percentage  of,  23 

Soil  mulches,  132 


264 


INDEX 


Soils,  7 

adapted  to  particular  crops,  8, 

21 

alkaline,  161 
character  of  indicated  by  native 

vegetation,  20 

humid  and  arid,  compared,  19 
hardpan  in,  18 

of  arid  and  semi-arid  regions,  18 
open  space  in,  20 
typical,  19 

South  Dakota,  2,  3,  4 
Spray  irrigation,  102 

feeder  system  for,  106 

from  suspended  nozzle  lines,  106 

overhead  nozzle  lines,  104 

portable  nozzle  type,  102 

pumping  plants  for,  108 

sizes  and  capacities  of  pipes  for, 

105,  106 

stationary  nozzle  type  of,  103 
Stabler,  Herman,  163 
State  control  of  water,  16, 136 
Strawberries,  247 
cost  of,  249 
profits  of,  249 
Stubbs,  W.  C.,  240 
Stump  puLcr,  Hercules,  67 
Stumps,  blasting  out,  67 
Sub  irrigation,  95 
artificial,  96 
cement  pipe  for,  99 
natural,  100 

in  San  Luis  Valley,  Colo.,  100 
near  St.  Anthony,  Idaho,  100 
stop  boxes  for,  97 
wooden  conduits  for,  98 
Submerged  orifice,  120 
Supplemental  irrigation,  252 
Sugar  beets,  204 
care  of,  206 
cost  of  growing,  209 
harvesting,  208 
irrigation  of,  206 
preparing  soil  for,  205 
seeding,  205 


Sugar  beets,  siloing,  209 
cane,  238 

amount  of  water  applied  to, 

242 

cost  of  producing,  241 
cultivation  of,  241 
irrigation  of,  240 
planting,  239 
preparing  soil  for,  239 
Surface  pipe  method  of  irrigation,  84 
stands  and  valves  for,  85 
tension,  26 
Swingle,  W.  T.,  161 


Tait,  C.  E.,  47,  59,  63,  76,  85,  182 
Teele,  R.  P.,  2,  140 
Texas,  2,  3,  4 
Thorburn,  W.  S.,  219 
Transportation  facilities,  8 
Twombly,  S.  S.,  219 

U 

Units  of  measure,  115 
Utah,  2,  3,  4 


V-crowder,  37 


W 


Washington,  2,  3,  4 
Waste  of  water,  111 

continuous    delivery,  cause   of, 

114 

flat  rate  per  acre,  cause  of,  113 
seepage  losses,  cause  of,  111 
Water-bearing  strata,  57 
Water  for  domestic  use,  43 
rights,  13 

abandonment  of,  17 
acquirement  of,  15 
adjudication  of,  17 


INDEX 


265 


Water  rights,  doctrine  of,  14 

supply,  11 
Weirs,  116 

Cipolletti  or  trapezoidal,   117 

discharge  of,  table  of,  118,  119 
Wells,  45,  59 

casing,  59 

cost  of  casing,  59 

drilling,  60 


Wells,  in  rice  belt,  60 
Wickson,  E.  J.,  216 
Widtsoe,  J.  A.,  21,  24,  161,  256 
Williams,  Milo  B.,  55,  102,  253 
Wilting  coefficient,  23 
Windmills,  255 
Winsor,  L.  M. 
Wyoming,  2,  3,  4 


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